Lancet device

ABSTRACT

The lancet device includes a housing and a lancet having a puncturing element. The lancet is disposed within the housing and is adapted for axial movement between an initial or pre-actuated position wherein the puncturing element is retained within the housing, and a puncturing position wherein the puncturing element extends through a forward opening in the housing. The lancet device includes a drive spring disposed within the housing for biasing the lancet toward the puncturing position, and a retraction or return spring for returning the lancet to a position within the housing where the puncturing element is disposed within the housing. The retraction spring thereafter maintains engagement with the lancet to assist in preventing the puncturing element from again projecting outward from the forward opening in the housing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to medical puncturing devices, commonly referred to as lancets, which are used to take blood samples from patients and, more specifically, to a lancet device that is designed for ease of use with activation achieved during contact of the device in normal use.

2. Description of Related Art

Lancet devices are used in the medical field for puncturing the skin of a patient to obtain a capillary blood sample from the patient. Certain diseases, such as diabetes, require that the patient's blood be tested on a regular basis to monitor, for example, the patient's blood sugar levels. Additionally, test kits, such as cholesterol test kits, often require a blood sample for analysis. The blood collection procedure usually involves pricking a finger or other suitable body part in order to obtain the blood sample. Typically, the amount of blood needed for such tests is relatively small and a small puncture wound or incision normally provides a sufficient amount of blood for these tests.

Various lancet devices are commercially available to hospitals, clinics, doctors' offices, and the like, as well as to individual consumers. Such devices typically include a sharp-pointed member such as a needle, or a sharp-edged member such as a blade, that is used to make a quick puncture wound or incision in the patient's skin in order to provide a small outflow of blood. It is often physiologically and psychologically difficult for many people to prick their own finger with a hand-held needle or blade. As a result, lancet devices have evolved into devices that facilitate puncturing or cutting the skin of the patient upon the actuation of a triggering mechanism. In some devices, the needle or blade is kept in a standby position until it is triggered by the user, who may be a medical professional in charge of drawing blood from the patient, or the patient himself or herself. Upon triggering, the needle or blade punctures or cuts the skin of the patient, for example on the finger. Often, a spring is incorporated into the device to provide the “automatic” force necessary to puncture or cut the skin of the patient.

It is of the utmost importance in the medical field that such medical puncturing devices or lancets are in a sterile condition before use. Today, generally without exception, medical puncturing devices or lancets are manufactured and packaged in a sterilized condition before they are distributed to medical professionals and members of the public who have a need for such devices. The sterile packaging maintains the sterility of the device, ensuring that the surrounding environment does not contaminate it until use. In addition, it is also of increasing importance that the user or another person does not come into contact with the needle or blade after use of the device. With the concern over blood-borne diseases, medical professionals are required to take great care with medical devices that come into contact with the blood of patients. Thus, an important aspect of lancet design involves preventing the needle or blade of the device from wounding the user or another person after the blood sample is drawn from the patient. Once used, the needle or blade should be shielded to prevent the needle or blade from wounding the user or another person handling the device. Moreover, the lancet device should be disposable to eliminate the chances of disease transmission due to the needle or blade being used on more than one person. In this regard, the lancet device should ideally be designed for one firing, and have safety features to prevent reuse.

Advances have been made in recent years to increase safety in operating and handling used lancet devices. For example, lancet devices are currently available which are single shot devices that feature automatic ejection and retraction of the puncturing or cutting element from and into the device. Examples of such medical puncturing devices are disclosed in U.S. Pat. Nos. 6,432,120; 6,248,120; 5,755,733; and 5,540,709.

U.S. Pat. No. 6,432,120 to Teo discloses a lancet device that includes a lancet holder which contains a spring-loaded lancet structure. The spring-loaded lancet structure includes a single spring that effects the ejection and retraction of a lancet needle upon the triggering of the structure. U.S. Pat. No. 6,248,120 to Wyszogrodzki discloses a lancet device comprised of a housing, a shielding portion, a piston with a puncturing tip, and drive and return springs that eject and retract the piston, respectively, upon the breakage of internal wing elements in the housing. U.S. Pat. No. 5,755,733 to Morita discloses a lancet device that includes a combined holder and lancet structure. The lancet structure includes a lancet member with a puncturing tip and a compressible spring member that causes the lancet member to puncture the skin of a patient upon actuation of a pair of actuating arms.

U.S. Pat. No. 5,540,709 to Ramel discloses a lancet device that includes a housing enclosing a slidable trigger, which is used to trigger a compressed spring that powers a piercing lancet member to pierce the skin of a patient. The housing includes a pair of internal fingers that engage the body of the lancet member, which are then released of engagement with the lancet member body by axial force applied by the user to the slidable trigger. Other medical puncturing devices or lancets known in the art are disclosed in U.S. Pat. Nos. 4,869,249 and 4,817,603. The devices disclosed in these references include a cap that is used to protect a needle or to keep the needle sterile.

In view of the foregoing, a need generally exists in the medical field for a medical puncturing device that is easy for a user to manipulate and use while ensuring sterility before use and safe and secure disposal after use. Additionally, a need exists in the medical field for a simple, inexpensive, reliable, and disposable medical puncturing device for use in collecting blood samples.

SUMMARY OF THE INVENTION

The present invention is generally directed to a lancet device. The lancet device according to a first embodiment comprises a housing, a shield at least partially disposed within the housing and movably associated therewith, and a lancet disposed in the housing and axially movable through the shield. The lancet comprises a puncturing element, and is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The lancet device further comprises an actuator associated with the shield and in interference engagement with the lancet in the initial position. In operation, axial movement of the shield into the housing causes the actuator to move the lancet toward and contact the rearward end of the housing to at least partially compress the drive spring. Upon contact with the rearward end of the housing, further force applied to retract the shield into the housing causes failure of the interference engagement between the actuator and the lancet thereby releasing the at least partially compressed drive spring and permitting the drive spring to bias the lancet through the shield to the puncturing position. The actuator comprises a shearable element associated with a proximal end of the shield, and the shearable element may comprise at least one breakable shelf or tab providing the interference engagement with the lancet.

The lancet device according to a second embodiment comprises a housing, a shield at least partially disposed within the housing and movably associated therewith, with the shield comprising at least one internal tab, and a lancet disposed in the housing and axially movable through the shield. The lancet comprises a puncturing element, and is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure. The lancet is in interference engagement with the internal tab in the shield in the initial position. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. In operation, axial movement of the shield into the housing causes the lancet to move toward and contact the rearward end of the housing due to the interference engagement with the shield internal tab to at least partially compress the drive spring. Upon contact with the rearward end of the housing, further force or movement applied to retract the shield into the housing causes failure of the internal tab removing the interference engagement and releasing the at least partially compressed drive spring to bias the lancet through the shield to the puncturing position. The lancet may comprise a cutting element providing the interference engagement with the internal tab in the initial position of the lancet, and failure of the internal tab may be caused by the cutting element cutting through the internal tab.

The lancet device according to a third embodiment comprises a housing, a shield at least partially disposed within the housing and movably associated therewith, and a lancet disposed in the housing and axially movable through the shield and comprising a puncturing element. The lancet is generally adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The lancet device further comprises an actuator in interference engagement with the lancet in the initial position and maintains the drive spring in an at least partially compressed state in the initial position of the lancet. The actuator comprises a sleeve portion associated with the housing and at least one elastic element in interference engagement with the lancet. In operation, axial movement of the shield into the housing causes the shield to move the elastic element radially outward from the lancet releasing the interference engagement therewith, and thereby releasing the at least partially compressed drive spring to bias the lancet through the shield to the puncturing position. The sleeve portion and elastic element may be formed integrally and connected, for example, by a living hinge.

The lancet device according to fourth embodiment comprises a housing and a lancet disposed in the housing and axially movable through the housing and comprising a puncturing element. The lancet is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a front opening in the housing for a puncturing procedure. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The drive spring is held in at least partially compressed state between the rearward end of the housing and the lancet by an interference engagement between the lancet and housing. The lancet device further comprises an actuator pivotally connected to the housing and in contact engagement with the lancet in the initial position for causing release of the drive spring. In operation, movement, typically depression, of the actuator causes pivotal movement thereof into the housing causing at least a portion of the lancet to move downward in the housing until the lancet is released of interference engagement with the housing, thereby releasing the at least partially compressed drive spring to bias the lancet through the housing to the puncturing position. The lancet may comprises at least one outward-extending guide tab and the housing may define an internal guide channel comprising a longitudinal main channel and a generally transverse side channel, such that the interference engagement comprises the guide tab engaging a corner or vertex defined generally at the intersection of the main channel and side channel.

The lancet device according to a fifth embodiment comprises a housing having an internal cam surface at a rearward end thereof, a shield at least partially disposed within the housing and movably associated therewith, and a lancet disposed in the housing and axially movable through the shield and comprising a puncturing element. The lancet is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure. A drive spring is disposed between the rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The lancet device further comprises an actuator associated with a proximal end of the shield disposed in the housing and in interference engagement with the lancet in the initial position thereof. In operation, axial movement of the shield into the housing causes the actuator to move the lancet toward the rearward end of the housing to at least partially compress the drive spring while simultaneously interacting with the internal cam surface. Continued interaction with the internal cam surface during the shield axial movement further moves the actuator to a position within the housing where the interference engagement between the actuator and the lancet is released, thereby releasing the at least partially compressed drive spring and permitting the drive spring to bias the lancet through the shield to the puncturing position. The actuator may comprise a plate member slidably associated with the shield proximal end and defining a keyhole for permitting passage of the lancet therethrough to release the interference engagement.

The lancet device according to a sixth embodiment comprises a housing and a lancet disposed in the housing and axially movable through the housing. The lancet device comprises a puncturing element, and is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a front opening in the housing for a puncturing procedure. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The lancet device further comprises an actuator associated with the housing and in interference engagement with the lancet in the initial position. The interference engagement between actuator and lancet maintains the drive spring in at least a partially compressed state between the rearward end of the housing and the lancet in the initial position. In operation, movement, typically depression, of the actuator into the housing moves the actuator to a position within the housing where the interference engagement between the actuator and the lancet is released, thereby releasing the at least partially compressed drive spring and permitting the drive spring to bias the lancet through the shield to the puncturing position. The actuator may comprise a lever member pivotally connected to the housing and a plate member depending into the housing. The plate member defines a keyhole for permitting passage of the lancet therethrough to release the interference engagement. The lancet device, according to a seventh embodiment, may include the actuator comprising a depressible button associated with the housing and a plate member depending into the housing, with the plate member defining a keyhole for permitting passage of the lancet therethrough to release the interference engagement.

The lancet device according to an eighth embodiment comprises a housing, a lancet disposed in the housing and axially movable through the housing and comprising a puncturing element. The lancet is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a front opening in the housing for a puncturing procedure. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The drive spring is held in at least a partially compressed state between the rearward end of the housing and the lancet by an interference engagement between the lancet and housing. The lancet device further comprises an actuator connected or optionally integrated pivotally to the housing and adapted to sever the interference engagement between the lancet and housing for causing release of the drive spring. In operation, movement, typically depression, of the actuator causes pivotal movement thereof into the housing until the actuator severs the interference engagement between the lancet and housing thereby releasing the at least partially compressed drive spring to bias the lancet through the housing to the puncturing position. The actuator may comprise a lever member connected pivotally to the housing and comprising a depending cutting edge for severing the interference engagement between the lancet and housing.

The lancet device according to a further embodiment comprises a housing and a lancet disposed within the housing and comprising a puncturing element. The lancet is adapted for axial movement between an initial, pre-actuated position wherein the puncturing element is retained within the housing and a puncturing position wherein the puncturing element extends through a front opening the housing. A drive spring is disposed between a rearward end of the housing and the lancet for biasing the lancet toward the puncturing position. The lancet device further comprises a retaining hub retaining the lancet in the pre-actuated position. The retaining hub is adapted to retain the lancet against the bias of the drive spring, and comprises a pivotal cam element. The cam element is in interference engagement with the lancet in the pre-actuated position of the lancet. In operation, axial movement of the housing toward the retaining hub causes the cam element to pivot, thereby moving the lancet toward the rearward end of the housing to at least partially compress the drive spring and releasing the cam element from interference engagement with the lancet, permitting the drive spring to drive the lancet through the housing toward the puncturing position. The cam element may define a recess or notch which releases the cam element from the interference engagement with the lancet when the cam element is pivoted to align the recess with an interfering on the lancet.

The lancet device may further comprise an internal contact within the housing and axial movement of the housing toward the retaining hub causes the internal contact within the housing to pivot the cam element. The cam element may comprise a contact surface for engagement with the internal contact of the housing. The internal contact of the housing may comprise an integrally formed cam surface for cooperating engagement with the contact surface of the cam element. The retaining hub may comprise an annular rim, generally defined by a pair of opposed support members connected by a pair of pivotal cam elements. The cam elements may comprise pivotal shafts connecting the support members.

The lancet device according to a final embodiment generally comprises a housing including an internal actuation member, a shield at least partially disposed within the housing and movably associated therewith, a lancet disposed in the housing and axially movable through the shield, and a rotation element. The lancet includes a puncturing element and is adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing, and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure. A drive spring is typically disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position. The lancet is typically in interference engagement with the rotation element in the initial position. In operation, axial movement of the shield into the housing causes the actuation member to rotate the rotation element relative to the lancet to a release position releasing the interference engagement between the lancet and rotation element, thereby permitting the drive spring to bias the lancet through the shield to the puncturing position.

The rotation element may be associated with the shield such that axial movement of the shield into the housing causes the drive spring to at least partially compress between the housing rearward end and lancet due to the interference engagement between the lancet and rotation element. The rotation element may be associated with a rearward end of the shield disposed in the housing.

The actuating member may comprise a cam element with a cam surface and the rotation element may comprise a guide plate defining a cam guide recess for receiving the cam element, such that axial movement of the shield into the housing causes the cam surface to engage the cam guide recess an impart rotational motion to the guide plate. The lancet may comprise an actuation tab in interference engagement with the guide plate, and the guide plate may define a clearance slot, such that the interference engagement may be released when the guide plate rotates to the release position where the actuation tab aligns with the clearance slot.

The actuating member may comprise a cam element with a cam surface and the rotation element may comprise a cam follower, such that axial movement of the shield into the housing causes the cam surface to engage the cam follower an impart rotational motion thereto at least until the cam follower reaches the release position.

Further details and advantages of the invention will become clear from the following detailed description when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal cross-sectional view of a first embodiment of a lancet device showing the lancet device in an initial, pre-actuated state;

FIG. 2 is a longitudinal cross-sectional view of the lancet device of FIG. 1 taken along a perpendicular longitudinal axis to the cross-sectional view in FIG. 1;

FIG. 3 is a longitudinal cross-sectional view of the lancet device of FIG. 1 showing the lancet device in an initial stage of actuation;

FIG. 4 is a longitudinal cross-sectional view of the lancet device of FIG. 1 showing the lancet device immediately after actuation;

FIG. 5 is a longitudinal cross-sectional view of the lancet device of FIG. 1 showing the lancet device after actuation with a lancet of device partially exposed for a puncturing procedure;

FIG. 6 is a longitudinal cross-sectional view of the lancet device of FIG. 1 showing the lancet device in a final state after actuation;

FIG. 7 is a longitudinal cross-sectional view of a second embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 8 is a longitudinal cross-sectional view of the lancet device of FIG. 7 taken along a perpendicular longitudinal axis to the cross-sectional view in FIG. 7;

FIG. 9 is a longitudinal cross-sectional view of the lancet device of FIG. 7 showing the lancet device in the initial stage of actuation;

FIG. 10 is a longitudinal cross-sectional view of the lancet device of FIG. 7 with the lancet of device removed for viewing the interior of the device;

FIG. 11 is a longitudinal cross-sectional view of the lancet device of FIG. 7 showing the lancet device after actuation with the lancet of device partially exposed for a puncturing procedure;

FIG. 12 is a longitudinal cross-sectional view of the lancet device of FIG. 7 showing the lancet device in the final state after actuation;

FIG. 13 is a longitudinal cross-sectional view of a third embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 14 is a longitudinal cross-sectional view of the lancet device of FIG. 13 showing the lancet device in the initial stage of actuation;

FIG. 15 is a longitudinal cross-sectional view of the lancet device of FIG. 13 showing the lancet device in a later stage of actuation;

FIG. 16 is a cross-sectional view of the lancet device of FIG. 13 showing the lancet device immediately after actuation;

FIG. 17 is a longitudinal cross-sectional view of the lancet device of FIG. 13 showing the lancet device after actuation with the lancet of the device partially exposed for a puncturing procedure;

FIG. 18 is a longitudinal cross-sectional view of the lancet device of FIG. 13 showing the lancet device in the final state after actuation;

FIG. 19 is a longitudinal cross-sectional view of a fourth embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 20 is a longitudinal cross-sectional view of the lancet device of FIG. 19 showing the lancet device in the initial stage of actuation;

FIG. 21 is a cross-sectional view of the lancet device of FIG. 19 showing the lancet device immediately after actuation;

FIG. 22 is a longitudinal cross-sectional view of the lancet device of FIG. 19 with the lancet of the device removed for viewing the interior of the device;

FIG. 23 is a longitudinal cross-sectional view of the lancet device of FIG. 19 showing the lancet device after actuation with the lancet of the device partially exposed for a puncturing procedure;

FIG. 24 is a longitudinal cross-sectional view of a fifth embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 25 is longitudinal cross-sectional view of the lancet device of FIG. 24 taken along a perpendicular longitudinal axis to the cross-sectional view in FIG. 24;

FIG. 26 is a transverse cross-sectional view of the lancet device of FIG. 24 showing the lancet device in the initial stage of actuation with the lancet in an interference engagement within the device;

FIG. 27 is a transverse cross-sectional view of the lancet device of FIG. 24 showing the lancet device at the point of actuation with the lancet released of the interference engagement within the device;

FIG. 28 is a longitudinal cross-sectional view of the lancet device of FIG. 24 showing the lancet device in the initial stage of actuation

FIG. 29 is a longitudinal cross-sectional view of the lancet device of FIG. 24 showing the lancet device at the point of actuation;

FIG. 30 is a longitudinal cross-sectional view of the lancet device of FIG. 24 showing the lancet device after actuation with the lancet of the device partially exposed for a puncturing procedure;

FIG. 31 is a longitudinal cross-sectional view of a sixth embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 32 is a second longitudinal cross-sectional view of the lancet device of FIG. 31 showing the lancet device in the initial, pre-actuated state;

FIG. 33 is a transverse cross-sectional view of the lancet device of FIG. 31 showing the lancet device in the initial stage of actuation with the lancet in an interference engagement within the device;

FIG. 34 is a transverse cross-sectional view of the lancet device of FIG. 31 showing the lancet device at the point of actuation with the lancet released of the interference engagement within the device;

FIG. 35 is a longitudinal cross-sectional view of the lancet device of FIG. 31 showing the lancet device in the initial stage of actuation;

FIG. 36 is a longitudinal cross-sectional view of the lancet device of FIG. 31 showing the lancet device at the point of actuation;

FIG. 37 is a longitudinal cross-sectional view of the lancet device of FIG. 31 showing the lancet device after actuation with the lancet moving within the device toward a puncturing position;

FIG. 38 is a longitudinal cross-sectional view of a seventh embodiment of the lancet device showing the lancet device in the initial, pre-actuated state;

FIG. 39 is a longitudinal cross-sectional view of the lancet device of FIG. 38 showing the lancet device in the initial stage of actuation with the lancet in an interference engagement within the device;

FIG. 40 is a transverse cross-sectional view of the lancet device of FIG. 38 showing the lancet device at the point of actuation with the lancet released of the interference engagement within the device;

FIG. 41 is a longitudinal cross-sectional view of the lancet device of FIG. 38 showing the lancet device after actuation with the lancet moving within the device toward a puncturing position;

FIG. 42 is a longitudinal cross-sectional view of the lancet device of FIG. 38 showing the lancet device after actuation with the lancet of device in the puncturing position for a puncturing procedure;

FIG. 43 is a longitudinal cross-sectional view of the lancet device of FIG. 38 showing the lancet device in the final state after actuation;

FIG. 44 is a perspective view of an eighth embodiment of the lancet device;

FIG. 45 is a perspective view of the lancet device of FIG. 44 with a sterile cover associated with the internal lancet removed;

FIG. 46 is an exploded perspective view of the lancet device of FIG. 44;

FIG. 47 is a perspective view of a portion of the lancet device of FIG. 44 showing an actuator, a drive spring, and the lancet of the device;

FIG. 48 is a longitudinal cross-sectional view of the lancet device of FIG. 44 showing the lancet device in the initial, pre-actuated state;

FIG. 49 is a longitudinal cross-sectional view of the lancet device of FIG. 44 taken along a perpendicular longitudinal axis to the cross-sectional view in FIG. 48;

FIG. 50 is a longitudinal cross-sectional view of the lancet device of FIG. 44 showing the lancet device at the point of actuation;

FIG. 51 is a longitudinal cross-sectional view of the lancet device of FIG. 44 showing the lancet device after actuation with the lancet of the device partially exposed for a puncturing procedure;

FIG. 52 is a longitudinal cross-sectional view of the lancet device of FIG. 44 showing the lancet device in the final state after actuation;

FIG. 53 is a perspective view of a further embodiment of the lancet device;

FIGS. 54A-54C are bottom, side, and end views, respectively, of a retaining hub used in the lancet device shown in FIG. 53;

FIG. 55 is a perspective view of the retaining hub shown in FIGS. 54A-54C

FIG. 56 is a perspective view of a final embodiment of the lancet device;

FIG. 57 is a longitudinal cross-sectional view of the lancet device of FIG. 56;

FIG. 58 is a transverse cross-sectional view of the lancet device of FIG. 56 taken along line 58-58 in FIG. 57;

FIG. 59 is an exploded and partial cross-sectional view of the lancet device of FIG. 56 showing a rear cap, guide plate and shield of the lancet device;

FIG. 60 is a perspective view of a lancet used in the lancet device of FIG. 56;

FIG. 61 is a perspective view of a rearward portion of the lancet of FIG. 60 showing the lancet associated with the shield and guide plate shown in FIG. 59;

FIG. 62 is a side view of the assembled structure shown in FIG. 61 additionally including the rear cap shown in FIG. 59;

FIG. 63 is a perspective view of a rearward end of a shield with a lancet movable through the shield in accordance with the lancet device of FIG. 56;

FIG. 64 is a perspective view of a forward end of the shield of the lancet device of FIG. 56;

FIGS. 65A and 65B are longitudinal and transverse cross-sectional views, respectively, of the lancet device of FIG. 56 showing the lancet device in an initial, pre-actuated state;

FIGS. 66A and 66B are longitudinal and transverse cross-sectional views, respectively, of the lancet device of FIG. 56 showing the lancet device in an initial stage of actuation; and

FIGS. 67A and 67B are longitudinal and transverse cross-sectional views, respectively, of the lancet device of FIG. 56 showing the lancet device at the point of actuation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of the description hereinafter, spatial orientation terms, if used, shall relate to the embodiment of the invention as it is oriented in the accompanying drawing figures. However, it is to be understood that the invention may assume many alternative variations and embodiments except where expressly specified to the contrary. It is also to be understood that the specific devices and embodiments illustrated in the accompanying drawing figures and described herein are simply exemplary embodiments of the invention, and wherein like elements are designated with like reference numerals and an accompanying alphabetic designation.

Referring to FIGS. 1-6, a lancet device 10 a according to a first embodiment is generally shown. The lancet device 10 a generally includes a housing 12 a, a shield 14 a movably associated with the housing 12 a, and a lancet 70 a movably disposed in the housing 12 a. As described in greater detail herein, shield 14 a is movably associated with the housing 12 a, and is at least partially disposed within housing 12 a. The shield 14 a typically extends partially outward from the housing 12 a, while the lancet 70 a is contained within housing 12 a and is axially movable through the shield 14 a.

The housing 12 a is generally in the form of an elongated body, referred to hereinafter as main body 20 a. The main body 20 a has a generally cylindrical and hollow configuration. The main body 20 a has a distal or forward end portion 22 a, and a rear cap 24 a forming a proximal or rearward end portion 26 a of the main body 20 a. The interior of main body 20 a is generally open and comprises an internal cavity or bore 28 a. The internal cavity 28 a is closed at the rearward end due to the presence of rear cap 24 a, and includes a front opening 30 a defined by a forward end portion 22 a of main body 20 a, and through which shield 14 a extends. Main body 20 a and rear cap 24 a may be integrally formed. Alternatively, main body 20 a and rear cap 24 a may be separate elements that are affixed together to form housing 12 a, which facilitates assembly of lancet device 10 a. As examples, main body 20 a and rear cap 24 a may be affixed together through an appropriate medical grade adhesive, or connected using inter-engaging structures providing a mechanical engagement therebetween, such as a friction-fit or a snap-fit connection. For example, main body 20 a may include an annular rim 32 a defining an annular groove 34 a, and rear cap 24 a may include a mating annular rim 36 a having a mating annular lip 38 a as mating elements. When main body 20 a and rear cap 24 a are connected, annular lip 38 a extends within the rear open end of main body 20 a, with annular lip 38 a snap-fitting over annular rim 32 a and into annular groove 34 a of main body 20. It should be understood that the arrangement of such elements is merely exemplary and may be reversed, and it is contemplated that other inter-fitting mechanical engagement arrangements may be used to connect the main body 20 a and rear cap 24 a. Main body 20 a further comprises an internal ridge 40 a, typically a perimetrically-extending ridge 40 a forward of annular groove 34 a, the purpose and function of which will be described herein. Further, main body 20 a of housing 12 a may include a forward rim 42 a formed as part of forward end potion 22 a and which defines front opening 30 a.

As noted previously, shield 14 a extends outward at least partially from front opening 30 a in the forward end portion 22 a of main body 20 a. Shield 14 a is a generally cylindrical, hollow structure comprising a shield body 50 a having a distal or forward end 52 a and a proximal or rearward end 54 a, and defines an internal cavity or bore 56 a extending therethrough. The forward end 52 a of shield body 50 a defines a partial forward end wall 58 a defining a forward opening 60 a, through which a puncturing element of lancet 70 a extends when lancet device 10 a is actuated by a user as will be discussed in more detail herein. The forward end wall 58 a generally defines a small contact area about forward opening 60 a for contacting an intended puncture area on a patient's body. The reduced contact area may be made smaller (i.e., reduced in surface area) by providing a plurality of peripheral indentations (not shown) formed perimetrically in shield 14 a. The external surface features of housing 12 a and shield 14 a may be formed in accordance with the ergonomic features and structure disclosed in co-pending application Ser. No. 11/123,849, filed Nov. 30, 2004, entitled “Lancet Device”, and naming Bradley Wilkinson as inventor. The disclosure of the foregoing “Lancet Device” application is incorporated herein by reference thereto.

The shield 14 a is axially and slidably movable within housing 12 a. The shield 14 a and housing 12 a may be coaxially associated, with the shield 14 a and housing 12 a coaxially disposed around a common Central Axis A. The shield 14 a and housing 12 a may each be generally cylindrically shaped. A shearable element 62 a is further associated with shield 14 a. In particular, shearable element 62 a is disposed at the rearward end 54 a of shield body 50 a and engages a rear rim 63 a of shield body 50 a. Shearable element 62 a comprises an annular sleeve portion 64 a that extends axially in a distal direction along the outer surface of shield body 50 a. The annular sleeve 64 a receives the rearward end 54 a of shield body 50 a so as to be positioned between shield body 50 a and main body 20 a of housing 12 a. In particular, the inner surface of annular sleeve 64 a engages a proximally-extending portion of the outer surface of shield body 50 a at the rearward end 54 a of shield body 50 a, while the outer surface of shearable element 62 a slidably cooperates with the inner surface of main body 20 a of housing 12 a. Shearable element 62 a further typically comprises two opposing and inward-projecting breakable shelves or wings 66 a that engage lancet 70 a as described further herein. While shearable element 62 a is shown with two opposing and inward-extending shelves or wings 66 a, it will be appreciated that only one shelf or wing 66 a is necessary for interference engagement with the lancet 70 a as described herein. Breakable shelves or wings 66 a may comprise a weakened area or score line 67 a for allowing the shelves 66 a to break (i.e., fail) when sufficient downward pressure is applied thereto as discussed herein. Breakable shelves or wings 66 a are generally inwardly radially-extending cantilevers which may be made of a similar or dissimilar material compared to that chosen for shield 14 a.

Shearable element 62 a is adapted to slide in combination with shield body 50 a in main body 20 a of housing 12 a when axial motion is imparted to shield body 50 a, for example by axially retracting (i.e., inserting) shield body 50 a into main body 20 a to actuate the lancet device 10 a as described herein. For this purpose and to properly engage the rear rim 63 a on the rearward end 54 a of shield body 50 a, shearable element 62 a comprises an abutment recess 68 a defined by sleeve portion 64 a which engages the proximal or rearward end 54 a of shield body 50 a, and rear rim 63 a in particular. Accordingly, any axial motion applied to shield body 50 a to retract (i.e., insert) shield body 50 a into main body 20 a of housing 12 a will be transmitted to shearable element 62 a through the interference engagement of rear rim 63 a in abutment recess 68 a. As a result, shearable element 62 a will slide within main body 20 a of housing 12 a along with shield body 50 a when axial motion applied thereto for actuating the lancet device 10 a. The captured portion of shield body 50 a may be secured in sleeve portion 64 a of shearable element 62 a so that there is tight engagement between these elements and ensuring that axial motion imparted to shield body 50 a will be transmitted to shearable element 62 a. For example, a medical grade adhesive or mechanical locking engagement may be provided between the inner surface of sleeve portion 64 a and the captured portion (i.e., outer surface) of shield body 50 a at the rearward end 54 a of shield body 50 a to ensure that these elements are secured together and move as a unit in main body 20 a of housing 12 a. Forward rim 42 a of main body 20 a of housing 12 a is formed to provide an interference engagement with the distal end of sleeve portion 64 a of shearable element 62 a to prevent shearable element 62 a and, consequently, shield body 50 a from axially sliding completely out of housing 12 a through front opening 30 a.

Lancet device 10 a further comprises a lancet 70 a disposed within the housing 12 a, and extending into shield 14 a. Lancet 70 a includes a puncturing element shown in the form of a lancet 72 a. Lancet 72 a comprises a puncturing end 74 a at the forward end thereof. Lancet 70 a is adapted for axial movement through the internal cavity 56 a of shield body 50 a between an initial position, wherein the puncturing end 74 a is disposed within shield body 50 a to a puncturing position wherein the puncturing end 74 a extends beyond the forward opening 60 a of shield body 50 a a sufficient distance to cause a puncture wound in a patient's body. Further details regarding the operation of lancet device 10 a and lancet 70 a are provided hereinafter.

The puncturing end 74 a of lancet 72 a is adapted for puncturing the skin of a patient, and may be in the form of a pointed end, needle tip, blade edge, and the like. Puncturing end 74 a may include a preferred alignment orientation, such as with a pointed end or a blade aligned in a specific orientation. In such an orientation, shield body 50 a and/or main body 20 a of housing 12 a may include target indicia corresponding to the alignment orientation of puncturing end 74 a. Indentations (not shown) in the shield body 50 a and/or indentations (not shown) in main body 20 a may function as such an alignment orientation, as described in co-pending application Ser. No. 11/123,849, previously incorporated by reference.

Lancet 70 a further includes a carrier body 76 a supporting lancet 72 a at the rearward end thereof. The carrier body 76 a and shield body 50 a may include corresponding guiding surfaces for guiding the movement of lancet 70 a in shield body 50 a. For example, carrier body 76 a may include guide tabs 78 a on an external surface thereof, with shield body 50 a defining corresponding guide channels 80 a extending longitudinally along an inner surface thereof for accommodating guide tabs 78 a slidably therein. The carrier body 76 may include a pair of guide tabs 78 a on opposing lateral sides thereof as illustrated, or a single guide tab 78 a, and shield body 50 a may include a corresponding pair of guide channels 80 a extending along opposing inner surfaces thereof corresponding to each of the guide tabs 78 a, or a single corresponding guide channel 80 a. It is contemplated that the arrangement of the guide tabs and channels 78 a, 80 a may be reversed, and multiple guide tabs-guide channels 78 a, 80 a (i.e., three or more) may also be used. The guide tabs 78 a and guide channels 80 a ensure that lancet 70 a is properly aligned within shield body 50 a, and guides the sliding axial movement of lancet 70 a within shield body 50 a and, further, may be used to prevent or resist rotational movement of carrier body 76 a in shield body 50 a. A distal facing surface 82 a on guide tabs 78 a engages shelves or wings 66 a on shearable element 62 a in the initial or pre-actuated state of lancet device 10 a until the shelves or wings 66 a are broken to release lancet 70 a. The carrier body 76 a further comprises a proximal or rearward end spring guide 86 a and a distal or forward end spring guide 88 a for engaging a drive spring and retraction spring, respectively, of lancet device 10 a as described herein. Spring guides 86 a, 88 a may be formed integral with the carrier body 76 a or be provided as distinct, separate elements and secured to the body of carrier body 76 a by means customary in the medical field as, for example, with medical grade adhesive or direct mechanical attachment.

Movement of the lancet 70 a through the lancet device 10 a is achieved through a biasing force provided by a drive spring 92 a. Drive spring 92 a is adapted to exert a biasing force against lancet 70 a to drive lancet 70 a through the lancet device 10 a toward the puncturing position, and is disposed between the rearward end of the housing 12 a and the lancet 70 a. Rear cap 24 a may include structure for alignment of and/or for maintaining drive spring 92 a in the proper orientation on rear cap 24 a. For example, rear cap 24 a may include an internal alignment structure (not shown) for correctly positioning the drive spring 92 a. The lancet 70 a, as indicated previously, includes proximal spring guide 86 a which engages the opposite end of drive spring 92 a in the initial or pre-actuated state of lancet device 10 a. In the initial state of lancet device 10 a, drive spring 92 a extends between rear cap 24 a and distal spring guide 86 a of carrier body 76 a. When the lancet 70 a is in the initial, pre-actuated state, drive spring 92 a is in a substantially unloaded, relaxed condition and exerts little to no biasing force on lancet 70 a. Upon compressing or “loading” the drive spring 92 a, the lancet device 10 a is placed into an armed or loaded state ready for a puncturing procedure as described in detail herein.

A retraction or return spring 94 a may further be provided at the forward or distal end of the lancet device 10 a, for retracting the lancet 70 a within the shield body 50 a after the lancet 70 a has moved distally to the puncturing position wherein the puncturing element 74 a extends outward from the distal or forward end 54 a of shield body 50 a a sufficient distance to cause a puncture wound in the patient. Retraction spring 94 a is adapted to be engaged by distal spring guide 88 a extending forward from carrier body 76 a during the forward movement of lancet 70 a, as described herein. The forward or distal end wall 58 a of shield body 50 a further comprises an axially rearward, or proximally-extending internal sleeve 96 a which defines a distal end pocket 98 for receiving retraction spring 94 a. The retraction spring 94 a is disposed in distal end pocket 98 a throughout the operation sequence of lancet device 10 a in a puncturing procedure. The retraction spring 94 a may be secured in distal end pocket 98 a through use of a medical grade adhesive or by mechanically securing retraction spring 94 a in distal end pocket 98 a. The drive and retraction springs 92 a, 94 a are typically compression springs capable of storing potential energy when in a compressed state.

Lancet device 10 a may further include a protective tab or cover 100 a for protectively covering the forward end of the lancet 70 a and, in particular, the puncturing end 74 a of lancet 72 a. The tab or cover 100 a protectively covers puncturing end 74 a to maintain sterility thereof prior to use. The tab or cover 100 a is typically a relatively thin and elongated structure that extends from carrier body 76 a through the forward opening 60 a in shield body 50 a for grasping by a user of the lancet device 10 a. Tab or cover 100 a may be integrally formed with the body of carrier body 76 a, for example, by being integrally formed with carrier body 76 a during a plastic molding process. The connection between tab or cover 100 a and carrier body 76 a may include a weakened area in the form of a perimeter groove or score line, along which the tab or cover 100 a is intended to break to remove the cover 100 a from carrier body 76 a. The tab or cover 100 a, as depicted, extends forward from distal spring guide 88 a of carrier body 76 a. Tab or cover 100 a is sized to extend axially through retraction spring 94 a. Various configurations of the tab or cover 100 a are described in co-pending application Ser. No. 11/123,849, previously incorporated by reference.

The respective elements of the lancet device 10 a are all typically formed of molded plastic material, such as a medical grade plastic material. The lancet 72 a may be constructed of any suitable material adapted for puncturing the skin, and is typically a surgical grade metal such as stainless steel.

Use and actuation of lancet device 10 a will now be described with continued reference to FIGS. 1-6. Lancet device 10 a is typically initially provided with cover 100 a extending distally from carrier body 76 a, and through forward opening 60 a in the forward end wall 58 a of shield body 50 a. In the initial, unarmed state of lancet device 10 a, the drive spring 92 a is substantially uncompressed (i.e., unloaded) and in a relaxed state. Drive spring 92 a extends from the inner side of rear cap 24 a to the carrier body 76 a and, more particularly, is disposed about proximal spring guide 86 a of carrier body 76 a. To use the lancet device 10 a in a puncturing procedure, the drive spring 92 a must be compressed and placed into a compressed, armed state to provide the biasing force needed to move the lancet 70 a through housing 12 a and shield 14 a. Further, in the initial state, the drive spring 92 a acts on spring guide 86 a substantially only to position lancet 70 a within main body 20 a of housing 12 a. More particularly, drive spring 92 a positions carrier body 76 a at a relatively fixed and stationary position within main body 20 a of housing 12 a, wherein the lancet 70 a occupies a generally fixed position relative to main body 20 a of housing 12 a and shield body 50 a of shield 14 a. Further, drive spring 92 a acting on spring guide 86 a of carrier body 76 a positions the carrier body 76 a such that guide tabs 78 a extending laterally from carrier body 76 a contact cantilevered shelves or wings 66 a on shearable element 62 a, which further serves to position shearable element 62 a and shield body 50 a at a substantially fixed position relative to main body 20 a. In particular, the drive spring 92 a acts on carrier body 76 a to position carrier body 76 a such that the distal surface 82 a on guide tabs 86 a is in interference engagement with shelves 66 a, and positions the shearable element 62 a and shield body 50 a at a generally fixed position relative to main body 20 a. Accordingly, until the user is ready to use the lancet device 10 a, shearable element 62 a and shield body 50 a are kept at a substantially constant relative position with respect to main body 20 a.

To use the lancet device 10 a, the user grasps opposing sides of housing 12 a, such as between a finger and thumb, and removes breakable cover 100 a. Cover 100 a is removed typically by moving cover 100 a in a combined twisting and pulling motion in forward opening 60 a defined in forward end wall 58 a of shield body 50 a to break the frangible connection with carrier body 76 a. Once the frangible connection is broken, the cover 100 a may be removed through the forward opening 60 a. The forward end wall 58 a of shield body 50 a may then be placed in contact with a location on the patient's body where it is desired to cause a puncture injury to initiate blood flow. If provided, target indicia may be aligned with the desired location of puncture.

Once placed against the body, the user exerts a downwardly directed force on main body 20 a of housing 12 a forcing shield body 50 a of shield 14 a to retract (i.e., depress) into housing 12 a. In particular, the user applies a downward directed force in the direction of Arrow X, thereby applying a force against the user's body (i.e., skin surface). Such force establishes an opposing force on forward end wall 58 a of shield body 50 a causing shield body 50 a to retract axially and proximally within main body 20 a of housing 12 a. As shield body 50 a retracts into main body 20 a, rearward end 54 a of shield body 50 a moves proximally (i.e., rearward) toward rear cap 24 a. The interference engagement between abutment recess 68 a on shearable element 62 a and the rear rim 63 a at the rearward end 54 a of shield body 50 a causes shearable element 62 a to move in combination with shield body 50 a toward rear cap 24 a. Substantially simultaneously, the interference engagement between guide tabs 78 a and shelves or wings 66 a begins to exert compressive pressure or force on drive spring 92 a. In particular, as the user applies downward force on housing 12 a, shield body 50 a and shearable element 62 a move rearward and transmit the opposing force to drive spring 92 a through the interference engagement between distal end surface 82 a on guide tabs 78 a and shelves 66 a, thereby beginning to compress drive spring 92 a between rear cap 24 a and carrier body 76 a.

As the entire lancet 70 a continues to move rearward, the interference engagement between guide tabs 78 a and shelves 66 a compresses drive spring 92 a between rear cap 24 a and carrier body 76 a and, more particularly, between proximal spring guide 86 a and rear cap 24 a. While the shelves or wings 66 a are intentionally formed to be broken (i.e., frangible), the shelves 66 a are formed with sufficient strength to withstand the force required to axially compress drive spring 92 a between proximal spring guide 86 a and rear cap 24 a a pre-selected distance without breaking. Further downward movement of main body 20 a of housing 12 a eventually causes the proximal spring guide 86 a to contact or “bottom out” against the inner side of rear cap 24 a. At this point, drive spring 92 a substantially reaches its maximum compression between proximal spring guide 86 a and rear cap 24 a and the lancet device 10 a is now “armed” or “loaded” sufficiently to carry out a puncturing procedure. Optionally, spring guide 86 a does not need to contact or “bottom out” against the inner side of rear cap 24 a, and drive spring 92 a may have sufficient stored potential energy to carry out the actuation of lancet device 10 a.

Once the proximal spring guide 86 a contacts the inner side of rear cap 24 a, continued downward force applied to main body 20 a of housing 12 a is applied entirely to breakable shelves or wings 66 a through the interference engagement with guide tabs 78 a. In particular, once the proximal spring guide 86 a contacts rear cap 24 a, the user's entire downward applied force is transmitted from main body 20 a (i.e., rear cap 24 a) to carrier body 76 a and, accordingly, guide tabs 78 a. The interference engagement between guide tabs 78 a and shelves 66 a focuses the downward applied force on the shelves 66 a, which will cause the shelves 66 a to yield, shear, or break (i.e., fail) in a distal or forward direction at weakened area 67 a and into internal cavity 56 a of shield body 50 a. At the moment the shelves or wings 66 a break, the restraining or compression force previously applied to drive spring 92 a due to the interference engagement between guide tabs 78 a and shelves 66 a is released, releasing the stored potential energy in drive spring 92 a to allow the drive spring 92 a to move lancet 70 a forward in shield body 50 a. Additionally, with the interference engagement broken between the guide tabs 78 a and shelves 66 a removed, the shearable element 62 a and shield body 50 a are free to retract rearward to engage annular rim 36 a on rear cap 24 a where their further rearward movement thereof is halted. As the shearable element 62 a and shield body 50 a move toward annular rim 36 a, shearable element 62 a rides over top of annular ridge 40 a on the inner surface of main body 20 a of housing 12 a. The engagement of shearable element 62 a with annular ridge 40 a increases the frictional engagement between the shearable element 62 a and main body 20 a of housing 12 a, thereby substantially fixing the position of shearable element 62 a and shield body 50 a relative to main body 20 a and inhibiting the shield body 50 a from moving forward again in main body 20 a. The frictional engagement between the outer surface of shearable element 62 a and annular ridge 40 a operates substantially as a frictional lock or brake to substantially prevent forward movement of shield body 50 a in main body 20 a after the shearable element 62 a and shield body 50 a retract fully into main body 20 a and engage rear cap 24 a.

With the stored potential energy in compressed drive spring 92 a released, the drive spring 92 a biases the lancet 70 a away from rear cap 24 a and through internal cavity 56 a in shield body 50 a. In particular, with the interference engagement between guide tabs 78 a and shelves 66 a removed, the biasing force of drive spring 92 a propels lancet 70 a downward and distally away from the rear cap 24 a axially through main body 20 a of housing 12 a and shield body 50 a of shield 14 a. During such movement, corresponding guide tabs 78 a and guide channels 80 a guide lancet 70 a axially through shield body 50 a. The biasing force acting on lancet 70 a is preferably sufficient to cause the puncturing end 74 a of lancet 72 a to project a sufficient distance and with sufficient kinetic energy from the forward opening 60 a in shield body 50 a to cause a puncture wound in the desired location on a patient's body. Moreover, during the propelling movement of lancet 70 a, proximal spring guide 86 a on carrier body 76 a of lancet 70 a releases from drive spring 92 a which remains connected to rear cap 24 a.

Further, as the lancet 70 a moves forward in the propelling movement, distal spring guide 88 a engages the rearward end of retraction spring 94 a. The biasing force provided by drive spring 92 a is at least in part applied to retraction spring 94 a by engagement of distal spring guide 88 a with the rearward end of retraction spring 94 a which causes the retraction spring 94 a to compress toward distal end pocket 98 a. The retraction spring 94 a is designed such that it may be compressed in whole or in part by the biasing force of drive spring 92 a propelling lancet 70 a, but still permits puncturing end 74 a of lancet 72 a to extend through forward opening 60 a in shield body 50 a a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow. Distal spring guide 88 a is sized to provide an abutment surface for abutting against internal sleeve 96 a supporting retraction spring 94 a to prevent lancet 70 a from axial movement entirely out of shield body 50 a through forward or front opening 60 a.

As indicated previously, retraction spring 94 a is typically a compression spring and will have sufficient resilience to return to a relaxed, unloaded state within shield body 50 a after the lancet 70 a extends to the puncturing position. Accordingly, once the retraction spring 94 a is compressed it will provide a return biasing force on the lancet 70 a by engagement with the distal spring guide 88 a on carrier body 76 a. The retraction spring 94 a thereby acts between the forward end wall 58 a of the shield body 50 a and distal spring guide 88 a on carrier body 76 a to cause sufficient or complete retraction of the lancet 70 a into shield body 50 a. In particular, retraction spring 94 a applies a return biasing force that retracts the puncturing end 74 a of lancet 72 a entirely within shield body 50 a. Moreover, as the retraction spring 94 a returns to a relaxed or unloaded state within shield body 50 a, the lancet 70 a is returned to a static position within shield body 50 a, wherein lancet 70 a is disposed at a relatively fixed and stationary position within shield body 50 a. Once retraction spring 94 a returns to a relaxed or uncompressed state, the retraction spring 94 a maintains the lancet 70 a disposed within the shield body 50 a with puncturing end 74 a shielded within shield body 50 a, and preventing further movement of lancet 70 a to the puncturing position. The lancet device 10 a is therefore safely protected from re-use and may be properly discarded, such as in an appropriate medical waste container.

Referring to FIGS. 7-12, a second embodiment of a lancet device 10 b is generally illustrated, and comprises the same basic components as lancet device 10 a described previously. Generally, lancet device 10 b comprises a housing 12 b, a shield 14 b movably associated with the housing 12 b, and a lancet 70 b movably disposed in housing 12 a and movable through shield 14 b. As the foregoing basic components of lancet device 10 b are substantially similar to the corresponding components of lancet device 10 a, only distinct differences between these components will be discussed herein, along with the use and sequence of operation of lancet device 10 b.

In contrast to lancet device 10 a, lancet device 10 b does not comprise a structure corresponding to shearable element 62 a discussed previously. Lancet device 10 b comprises the shield 14 a having a shield body 50 b with a rear ledge or rim 102 at shield proximal end 54 b. The rear ledge or rim 102 is adapted for interference engagement with forward rim 42 b at the forward end portion 22 b of main body 20 a of housing 12 a. The interference engagement of rear ledge 102 with forward rim 42 b is provided to prevent the shield body 50 b from axially sliding completely out of housing 12 b through front opening 30 b defined in forward rim 42 b prior to actuating lancet device 10 b. Rear rim 102 is sized such that it may contact and slidably engage the inner surface of main body 20 b when shield body 50 b is retracted (i.e., depressed) into main body 20 b, as will occur when the lancet device 10 b is actuated by a user.

A further difference over lancet device 10 a discussed previously lies in the interfering structure between lancet 70 b and shield 14 b used to place lancet device 10 b into an armed or loaded state, and thereafter cause actuation of lancet device 10 b. In lancet device 10 b, shield body 50 b comprises inward-extending shelves, wings, or internal tabs 104, which take the place of breakable shelves or wings 66 a on shearable element 62 a in lancet device 10 a. The internal tabs 104 are desirably formed integrally with the shield body 50 b, but may also be part of an additional, separate structure associated with shield body 62 a, for example associated with rear rim 102 and extending into central cavity or bore 56 b of shield body 50 b. While shield body 50 b is shown with two opposing and inward-extending internal tabs 104, it will be appreciated that only one internal tab 104 is necessary for engagement with the lancet 70 b in a similar manner to that described previously in connection with the breakable shelves or wings 66 a on shearable element 62 a.

In lancet device 10 a, guide tabs 78 a form the structure on lancet 70 a for an interference engagement with breakable shelves or wings 66 a, which initially just contact shelves 66 a under the position effect of drive spring 92 a in the initial or pre-actuated state of lancet device 10 a. In lancet device 10 b, guide tabs 78 b are further provided or formed with cutting elements 106 which may be cutting blades, edges, and the like. Cutting elements 106 may be formed integrally with guide tabs 78 b or, alternatively, be separate cutting structures secured to guide tabs 78 b by means customary in the medical device field, such as direct mechanical or adhesive attachment. The cutting elements 106 are adapted to cut, shear, or plastically deform internal tabs 104 in the internal cavity 56 b of shield body 50 b during actuation of lancet device 10 b to permit movement of lancet 70 b through shield body 50 b, and thereby conduct a puncturing procedure. Other than the foregoing structural differences, lancet device 10 b is substantially similar in all other respects to the structure of lancet device 10 a described previously.

With continued reference to FIGS. 7-12, use and operation of lancet device 10 b will now be discussed. Prior to use, cover 100 b extending distally from carrier body 76 b is removed by breaking the frangible connection with carrier body 76 b in the manner described previously and withdrawing cover 100 b from forward opening 60 b in forward end wall 58 b of shield body 50 b. The forward end wall 58 b of shield body 50 b may then be placed in contact with a target location on a patient's body. In the initial state of lancet device 10 b, the drive spring 92 b is substantially uncompressed (i.e., unloaded) and in a relaxed state. Drive spring 92 b extends from proximal spring guide 86 a of carrier body 76 a to rear cap 24 b. As discussed previously, in the initial state of lancet device 10 b, drive spring 92 a is in a relaxed condition and acts on spring guide 86 b substantially to position lancet 70 b at a stationary position within main body 20 b of housing 12 a, wherein the lancet 70 b occupies a generally fixed position relative to main body 20 b. Additionally, drive spring 92 b acts on spring guide 86 b on carrier body 76 b to position carrier body 70 a in main body 20 b such that guide tabs 78 b and more particularly, cutting elements 106 are in interference engagement with tabs or shelves 104 in the internal cavity 56 b of shield body 50 b. The interference engagement between cutting elements 106 and internal tabs 104 further operates to place shield body 50 b at a generally fixed and stationary position relative to main body 20 b. Accordingly, until the user is ready to use lancet device 10 b, shield body 50 b is kept substantially at a generally fixed and stationary position relative to main body 20 a by virtue of the interference engagement between guide tabs 78 b and internal tabs 104 in shield body 50 b.

To use the lancet device 10 b, the user grasps opposing sides of housing 12 b and exerts downwardly directed force on main body 20. This force causes an opposing force on forward end wall 58 b of shield body 50 b, causing shield body 50 b to retract axially within main body 20 a. As shield body 50 b retracts into main body 20 b, rearward end 54 a of shield body 50 a moves proximally (i.e., rearward) toward rear cap 24 b. Due to the interference engagement between guide tabs 78 b and internal tabs or shelves 104 and, more particularly, between cutting elements 106 on guide tabs 78 b and internal tabs or shelves 104, lancet 70 b also moves rearwardly toward rear cap 24 b. As the shield body 50 b moves rearward, the opposing force is applied to drive spring 92 b through the interference engagement between cutting elements 106 on guide tabs 78 a and internal tabs or shelves 104, thereby compressing drive spring 92 b between rear cap 24 b and carrier body 76 b. While internal tabs 104 are intended to cut-through or plastically deformed by cutting elements 106, they are formed with sufficient strength to withstand being cut-through or sheared-off by cutting elements 106 under the opposing force required to axially compress drive spring 92 b between proximal spring guide 86 b and rear cap 24 b. In other words, internal tabs or shelves 104 are formed to withstand the force required to compress drive spring 92 b a predetermined distance prior to the desired point of triggering. Further downward movement of housing 12 b eventually causes proximal spring guide 86 b to contact the inner side of rear cap 24 a. At this point, drive spring 92 ba substantially reaches its maximum compression with a maximum level of stored potential energy. Lancet device 10 b is now in an armed or loaded state sufficient to carry out a puncturing procedure.

Once the proximal spring guide 86 b contacts rear cap 24 b, the downward force applied to main body 20 b of housing 12 b is applied entirely to the interference engagement between cutting elements 106 and internal tabs 104. In particular, once proximal spring guide 86 b contacts rear cap 24 b, the user's entire downward applied force is transmitted from main body 20 b (i.e., rear cap 24 b) to carrier body 76 b and, accordingly, guide tabs 78 b and cutting elements 106. The downward cutting force on the internal tabs 104 is now sufficient to cut-through or plastically deform internal tabs 104. At the moment the internal tabs 104 are cut-through or plastically deformed, the opposing force applied to compress drive spring 92 b is released, thereby allowing drive spring 92 b to move lancet 70 b forward in shield 14 b. Additionally, with the interference engagement between guide tabs 78 b and internal tabs 104 removed, shield body 50 b is able to retract further rearward under the downward force still typically applied by the user to housing 12 b. The shield body 50 b ultimately moves rearward to a position engaging annular rim 36 b on rear cap 24 b where further rearward movement is halted. As the shield body 50 b moves toward annular rim 36 b on rear cap 24 b, rear rim 102 on the rearward end 54 b of shield body 50 b rides over top of annular ridge 40 b. The annular ridge 40 b thereafter forms a locking structure to inhibit or prevent subsequent forward movement of shield 50 b.

With the potential energy stored in drive spring 92 b by compression thereof released, the drive spring 92 b biases lancet 70 b away from rear cap 24 b and through shield body 50 b. During such propelling movement, the corresponding guide tabs 78 b and guide channels 80 b guide lancet 70 b axially through shield body 50 b. The biasing force applied to lancet 70 a is preferably sufficient to cause the puncturing end 74 b of lancet 72 b to project a sufficient distance and with sufficient force from the forward opening 60 b in shield body 50 b to cause a puncture wound at the target location on the patient's body. Moreover, during the propelling movement of lancet 70 b, proximal spring guide 86 b on carrier body 76 b releases from drive spring 92 b which remains connected to rear cap 24 b. Internal sleeve 96 b at the forward end wall 58 b defines a distal stop for engaging distal spring guide 88 b and prevents lancet 70 b from axial movement entirely out of shield body 50 b through forward opening 60 b.

As the lancet 70 b moves forward in the propelling movement, distal spring guide 88 b engages retraction spring 94 b. The biasing force applied to lancet 70 b by drive spring 92 b is at least in part applied to retraction spring 94 b by engagement of distal spring guide 88 b with retraction spring 94 b, which causes the retraction spring 94 b to compress toward distal end pocket 98 b. The retraction spring 94 a permits puncturing end 74 b of lancet 72 b to extend through forward opening 60 b in shield body 50 b a sufficient distance and with sufficient kinetic energy to puncture the skin of the patient and initiate blood flow, and thereafter return lancet 70 b to a substantially fixed and stationary position within shield 14 b. In particular, as the retraction spring 94 b returns to a relaxed or unloaded state within shield body 50 b, the lancet 70 a is retracted in shield 14 b and returned to a substantially fixed and stationary positioned within shield body 14 b. Thereafter, the engagement of retraction spring 94 b with distal spring guide 88 b maintains the lancet 70 b at a generally fixed and stationary position within shield body 50 b. This maintains puncturing end 74 b shielded within shield body 50 b, and prevents further movement of lancet 70 b to the puncturing position.

Referring to FIGS. 13-18, a third embodiment of a lancet device 10 c is generally illustrated, and comprises the same basic components as lancet devices 10 a, 10 b described previously. Generally, lancet device 10 c comprises a housing 12 c, a shield 14 c movably associated with the housing 12 c, and a lancet 70 c movably disposed in housing 12 c. As the foregoing basic components of lancet device 10 c are substantially similar to the corresponding components of lancet devices 10 a, 10 b only distinct differences between these components will be discussed herein, along with the general use and sequence of operation of lancet device 10 c.

In lancet devices 10 a, 10 b, lancets 70 a, 70 b are initially positioned at substantially fixed and stationary positions in housings 12 a, 12 b by drive springs 92 a, 92 b in the initial, pre-actuated states of these devices. In lancet devices 10 a, 10 b, drive springs 92 a, 92 b are initially in a relaxed, unloaded condition and act upon lancets 70 a, 70 b to position lancets 70 a, 70 b relative to housings 12 a, 12 b. Lancet devices 10 a, 10 b are only placed in an armed or loaded state when shields 14 a, 14 b are retracted (i.e., depressed) into housings 12 a, 12 b under the force applied by a user, which in turn causes lancets 70 a, 70 b to act upon drive springs 92 a, 92 b and compress and load the respective drive springs 92 a, 92 b with potential energy.

Lancet device 10 c is initially provided in an armed or loaded state, with lancet 70 c ready to be biased to a puncturing position by a compressed drive spring 92 c. In this initial armed state, drive spring 92 c is in a compressed (i.e., loaded) state, ready to bias the lancet 70 c through a puncturing procedure upon release. In particular, lancet device 10 c is provided with drive spring 92 c compressed between proximal spring guide 86 c on carrier body 76 c and rear cap 24 c. The lancet 70 c is secured against forward movement into shield 14 c by a locking or actuation structure 110 extending between housing 12 c and lancet 70 c. Actuator 110 prevents release of lancet 70 c and, correspondingly, maintains compression of drive spring 92 c until a user of the lancet device 10 c is ready to carry out a puncturing procedure.

Actuator 110 generally comprises a sleeve portion 112 and one or more pivotal splints or tabs 114, for example elastic splints, extending from the sleeve portion 112. Sleeve portion 112 is disposed in an annular wall recess 116 defined in the inner surface of main body 20 c of housing 12 c. Main body 20 c is formed with a generally thicker annular wall in lancet device 10 c in comparison to lancet devices 10 a, 10 b. Sleeve portion 112 may be secured in wall recess 116 by a medical grade adhesive and/or preferably by being captured axially between wall recess 116 and annular rim 36 c on rear cap 24 c and thereby frictionally held in wall recess 116. Actuator 110 is depicted with two generally inward-extending splints or tabs 114 engaging lancet 70 c. While this configuration is desirable, only one elastic splint 114 for engaging lancet 70 c is typically required, and additional splints 114 in excess of two may be also be provided.

The splints 114 extend generally rearward or in a proximal direction in main body 20 c and engage guide tabs 78 c on carrier body 76 c of lancet 70 c. Splints 114 are angled inward, in this instance, at approximately a 45° angle relative to Central Axis A to engage guide tabs 76 c in the initial state of lancet device 10 c. In particular, ends 118 of splints 114 engage guide tabs 78 c on carrier body 76 c to prevent lancet 70 c from releasing from the initial, armed state of lancet device 10 c and thereby maintain drive spring 92 c in a compressed state until lancet device 10 c is actuated by a user. Splints 114 are each connected by a hinge connection 120 to sleeve portion 112. The hinge connection 120 may be a living hinge as illustrated as an exemplary embodiment of this structure. Ends 118 of splints 114 engage a corner of guide tabs 78 c, such that distal movement of carrier body 76 c distally with respect to housing 12 c in absence of shield 14 c would cause splints 114 to generally compress between hinge connection 120 and the point of contact between guide tabs 78 c. As with lancet devices 10 a, 10 b, lancet device 10 c is actuated when a user depresses housing 12 c to retract (i.e., depress) shield 14 c therein. However, shield 14 c is now adapted to release actuator 110 between housing 12 c and lancet 70 c, thereby releasing compressed drive spring 92 c to bias the lancet 70 c through a puncturing procedure.

To facilitate actuation of lancet device 10 c, shield 14 c is adapted to engage and release actuator 110. For this purpose, shield body 50 c may be formed with a tapered rear rim 122 at shield proximal end 54 c. The tapered rear rim 120 is generally tapered in the same direction as splints 114 to engage the distal or forward facing sides of splints 114. The point of engagement for the tapered rear rim 122 is on splints 114 at a location between hinge connection 120 and the point of contact between guide tabs 78 c. The tapered rear rim 122 may define a taper of about 45° to correspond to the inward taper of splints 114. In the initial, armed state of lancet device 10 c, the tapered rear rim 122 is in contact with splints 114 so that any rearward movement of shield 14 c into housing 12 a will immediately act upon the actuator 110 and splints 114 in particular. While the rear rim 122 is illustrated with a defined taper, it will be appreciated that such taper may be omitted and shield body 50 c formed as a cylindrical structure with a flat or blunted rear rim 122.

With continued reference to FIGS. 13-18, use and operation of lancet device 10 c will now be discussed. As with previous embodiments, cover 100 c extending distally from carrier body 76 c is first removed by breaking the frangible connection with carrier body 76 c and withdrawing cover 100 c from forward opening 60 c in forward end wall 58 c of shield body 50 c. The forward end wall 58 c of shield body 50 c may then be placed in contact with the target location on the patient's body. As indicated, lancet device 10 c is initially provided in an armed state with lancet 70 c ready to initiate a puncturing procedure when compressed drive spring 92 c is released.

To carry out a puncturing procedure, the user grasps opposing sides of housing 12 c and exerts downwardly directed force in the direction of Arrow X on main body 20 c forcing shield body 50 c to retract into main body 20 c. This force causes an opposing force on forward end wall 58 c of shield body 50 c, causing shield body 50 c to retract axially within main body 20 c. As shield body 50 c retracts into main body 20 c, tapered rear rim 122 on rearward end 54 c of shield body 50 c and in engagement with splints 114 begins to move splints 114 radially outward toward sleeve portion 112. Continued rearward movement of shield body 50 c causes the splints 114 to continue their radial outward movement away from lancet 70 c until the splints 114 disengage from guide tabs 78 c and release the interference engagement therewith. The configuration of actuator 110 converts the axial movement of shield body 50 c into pivotal radial outward movement of splints 114 to effectuate actuation of lancet device 10 c.

With the potential energy in drive spring 92 c released, drive spring 92 c biases the lancet 70 c away from rear cap 24 c and through shield body 5 cb. During such propelling movement, corresponding guide tabs 78 c on carrier body 76 c and guide channels 80 c within shield body 50 c guide lancet 70 c axially through shield body 50 c. The biasing force imparted to lancet 70 c is preferably sufficient to cause the puncturing end 74 c of lancet 72 c to project a sufficient distance and with sufficient force from the forward opening 60 c of shield body 50 c to cause a puncture wound in the desired location on the patient's body. Moreover, during the propelling movement of lancet 70 c, proximal spring guide 86 c on carrier body 76 c releases from drive spring 92 c which remains connected to rear cap 24 c. Distal spring guide 88 c provides an abutment surface for engaging internal sleeve 96 c supporting retraction spring 94 c to prevent lancet 70 c from axial movement entirely out of shield body 50 c through forward opening 60 c.

As the lancet 70 c moves forward in the propelling movement, distal spring guide 88 c engages retraction spring 94 c. The biasing/propelling force provided by drive spring 92 c is at least in part applied to retraction spring 94 c by engagement of distal spring guide 88 c with retraction spring 94 c, which causes the retraction spring 94 c to compress toward distal end pocket 98 c. The retraction spring 94 c permits puncturing end 74 c of lancet 72 c to extend through forward opening 60 c in shield body 50 c a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow, and thereafter return lancet 70 c to a substantially fixed and stationary position within shield 14 b. In particular, as the retraction spring 94 c returns to a relaxed or unloaded state within shield body 50 c, the lancet 70 c is retracted in shield 14 c and returned to a generally stationary and fixed position within shield body 50 c. Thereafter, the engagement of retraction spring 94 c with distal spring guide 88 c maintains the lancet 70 c at a stationary and relatively fixed position within shield body 50 c and maintains puncturing end 74 c shielded within shield body 50 c preventing further movement of lancet 70 c to the puncturing position.

Referring to FIGS. 19-23, a fourth embodiment of a lancet device 10 d is generally illustrated, and generally comprises a housing 12 d and a lancet 70 d disposed in housing 12 d. Lancet device 10 d differs from lancet devices 10 a-c discussed previously, as lancet device 10 d is not actuated through the retraction (i.e., depression) of a shield element into housing 12 d. However, lancet device 10 d is similar to lancet device 10 c discussed immediately above because lancet device 10 d is initially provided in an armed or loaded state, with lancet 70 d ready to be biased to the puncturing position by drive spring 92 d upon release of an interfering structure. In this initial, armed state, drive spring 92 d is in a compressed (i.e., loaded) state, ready to bias the lancet 70 d through a puncturing procedure upon repositioning lancet 70 d with respect to an interfering structure or engagement between housing 12 d and lancet 70 d. However, the configuration of the housing 12 d, lancet 70 d, and drive spring 92 d differ from previous embodiments and these differences will now be described.

Housing 12 d of lancet device 10 d comprises an elongated main body 20 d that generally defines a cylindrical and hollow configuration. The main body 20 d has a distal or forward end portion 22 d, and a rear cap 24 d forming a proximal or rearward end portion 26 d of the main body 20 d. The interior of housing 12 d is generally open and comprises an internal cavity 28 d. The internal cavity 28 d is closed at the rearward end due to rear cap 24 d, and includes a front opening 30 d defined in forward end portion 22 d of main body 20 d, and through which lancet 70 d at least partially extends when lancet device 10 d is actuated. Main body 20 d and rear cap 24 d may be integrally formed. Typically, main body 20 d and rear cap 24 d are separate elements that are affixed together to form housing 12 d, as illustrated, which facilitates assembly of lancet device 10 d. As examples, main body 20 d and rear cap 24 d may be affixed together through an appropriate medical grade adhesive, and/or may be connected using inter-engaging structures providing a mechanical engagement therebetween, such as a friction-fit or a snap-fit construction. For example, main body 20 d may include an annular rim 32 d defining an annular groove 34 d, and the rear cap 24 a may include a mating annular rim 36 d having a mating annular lip 38 d as mating elements in much the same manner as described previously.

In contrast to previous embodiments, distal or forward end portion 22 c 1 of main body 20 d comprises an axially rearward-extending internal sleeve 98 d that defines a distal end pocket 98 d for receiving and supporting retraction spring 94 d. In previous embodiments, the retraction spring(s) were disposed in a distal end pocket formed as part of the forward end wall of the actuating shield structure. This structure is now provided at the forward end portion 22 d of main body 20 d of housing 12 d. Additionally, main body 20 d of housing 12 d further comprises an actuation structure or actuator 130 for causing actuation of lancet 70 d and corresponding release of drive spring 92 d. Actuator 130 generally comprises an actuating button or lever 132 that is typically pivotally associated with main body 20 d. The pivotal association with main body 20 d may be in the form of a living hinge or equivalent structure and lever 132 may thus be integrally formed with main body 20 d. A tab member 134 depends from an inner side of actuating lever 132 for engaging lancet 70 d and causing actuation of the same. In particular, lever 132 is pivotally connected to main body 20 d so that the lever 132 may be depressed inward into internal cavity 28 d in main body 20 d, such that tab member 134 interacts with lancet 70 d to cause actuation or release of lancet 70 d.

Main body 20 d of housing 12 d includes opposing inner sidewalls 136 each defining an internal guide channel 138 for guiding movement of lancet 70 d within main body 20 d. Guide channels 138 may be formed as grooves or recesses in the inner sidewalls 136, or be formed in a structure extending inward from the respective sidewalls 136. Guide channels 138 are generally L-shaped and comprise a longitudinally extending main channel 140 and a generally transversely extending side channel 142. Main channel 140 extends distally forward from an area proximate to tab member 134 to a location proximate to retraction spring 94 d. Main channel 140 defines an abutment surface or stop 144 in guide channels 138 to provide a stop for carrier body 76 d of lancet 70 d to prevent axial movement of the lancet 70 d entirely out of main body 20 d through front opening 30 d.

Side channel 142 is contiguous with main channel 140 and extends approximately oblique to transverse to main channel 140. Side channel 142 extends upward in a direction towards lever 132. While side channel 142 is formed generally oblique to main channel 140, side channel 142 and main channel 140 define a tapered corner or vertex 146 at their intersection. The corner 146 defines an angle of less than about 90°. The opposing side channels 142 in main body 20 d are used to initially receive guide tabs 78 d on carrier body 76 d for maintaining carrier body 76 d in a dynamically stable and balanced position, thereby opposing the force acting on guide tabs 78 d by drive spring 92 d, and restraining compressed drive spring 92 d. Corner 146 is used to define the transition between main channel 140 and side channel 142. Movement of guide tabs 78 d towards side channels 142 allows carrier body 76 d to transition from a position of dynamic stability to a position of dynamic instability. Accordingly, side channels 142 initially maintain the positioning of guide tabs 78 d, with guide tabs 78 d in interference engagement with corners or vertexes 146 to maintain the positioning of guide tabs 78 d until lancet device 10 d is to be actuated.

Lancet 70 d is formed in a generally analogous manner as previous embodiments and comprises a lancet 72 d with a puncturing end 74 d at the forward end thereof, and a carrier body 76 d supporting lancet 72 d at the rearward end thereof. The carrier body 76 d comprises a pair of guide tabs 78 d on an external surface thereof that engage guide channels 138. Lancet 70 d is adapted for axial movement through the internal cavity 28 d of main body 20 d between an initial position wherein guide tabs 78 d are disposed in side channels 142 and the puncturing end 74 a is disposed entirely within main body 20 d, to a puncturing position wherein the puncturing end 74 d extends beyond the front opening 30 d in main body 20 d a sufficient distance to cause a puncture wound on a patient's body while guide tabs 78 d remain disposed in main channels 140. Further details regarding the operation of lancet device 10 d and the movement of lancet 70 d are provided hereinafter.

Carrier body 76 d further comprises a proximal or rear rim 148 at the rearward end thereof. Rim 148 defines the forward end of proximal spring guide 86 d and typically has a diameter larger than the diameter of distal spring guide 88 d of carrier body 76 d. Rim 148 is provided as a contact structure or surface on lancet 70 d for engagement by tab member 134 to cause actuation of lancet device 10 d. The diameter of rim 148 is also typically sized to be at least equal to the diameter of drive spring 92 d and provides a contact structure or surface that restrains compressed drive spring 92 d in the initial state of lancet 70 d. During actuation of lancet device 10 d, drive spring 92 d acts against rear rim 148 to bias lancet 70 d to the puncturing position, as described herein. Moreover, carrier body 76 d additionally comprises two opposing posts 150 cooperating with guide channels 138, and main channels 140 in particular. Posts 150 engaged in guide channels 138 permit at least a limited amount of pivotal movement by carrier body 76 d about an axis passing through posts 150, and maintain lancet 70 d associated with guide channels 138 until guide tabs 78 d align with main channels 140 during the actuation sequence of lancet device 10 d.

In the initial state of lancet device 10 d, drive spring 92 d is at least partially compressed between rear rim 148 on carrier body 76 d and rear cap 24 d, and typically has sufficient stored potential energy to conduct a skin-puncturing procedure. The rearward or proximal end of drive spring 92 d is typically secured to rear cap 24 d in the manner discussed previously in this disclosure. The forward or distal end of drive spring 92 d is associated with carrier body 76 d and may be secured to rear rim 148 by similar means discussed previously, as by suitable adhesive or direct mechanical attachment. Drive spring 92 d generally defines an off-axis or off-center spring arrangement, wherein drive spring 92 d extends at upward angle toward lever 132. Drive spring 92 d is stabilized in the off-center and compressed (i.e., loaded) arrangement by engagement of guide tabs 78 d in side channels 142 of guide channels 138. Corners 146 define an interfering engagement and point of transition for guide tabs 78 d to maintain drive spring 92 d in a compressed (i.e., loaded) state and in the off-center configuration. The acute angle defined by corner 146 defines a receiving notch 152 for guide tabs 78 d to prevent guide tabs 78 d from readily releasing from side channels 142 until intended actuation by a user. Thus, engagement of guide tabs 78 d in guide channels 138 forms an interfering structure to secure lancet 70 d against forward movement in main body 20 d and, correspondingly, maintains compression of drive spring 92 d until a user of the lancet device 10 d is ready to carry out a puncturing operation.

With continued reference to FIGS. 19-23, use and operation of lancet device 10 d will now be discussed. As with previous embodiments, a cover (not shown) extending distally from carrier body 76 d may be provided with carrier body 76 d. As with previous embodiments, such a cover is removed by breaking the frangible connection with carrier body 76 d and withdrawing the cover from front opening 30 d in main body 20 d. The forward end rim 42 d of main body 20 d may then be placed in contact with the target location on a patient's body. As indicated previously, lancet device 10 d is initially provided in an armed state with lancet 70 d ready initiate a puncturing procedure when compressed drive spring 92 d is released.

To carry out a puncturing procedure, the user grasps opposing sides of housing 12 d and exerts downwardly directed force on lever 132 pivotally connected to main body 20 d, causing lever 132 to depress into internal cavity 28 d of main body 20 d. As lever 132 is depressed into main body 20 d, tab member 134 interacts with rear rim 148 on carrier body 76 d. In particular, the downward force applied to lever 132 causes tab member 134 to move rear rim 148 downward in the internal cavity 28 d. As rear rim 148 of carrier body 76 d moves downward in internal cavity 28 d of main body 20 d, the carrier body 76 d will substantially simultaneously pivot about posts 150 in main channel 140 of guide channels 138. Also substantially simultaneously, guide tabs 78 d received in side channels 142 slide downward in side channels 142 until passing corners 146 which has the effect of moving carrier body 76 d from a first state of being dynamically balanced to a second state of being dynamically unbalanced, thereby allowing drive spring 92 d to propel carrier body 76 d through main body 20 d until the puncturing end 74 d of lancet 72 d projects through front opening 30 d in main body 20 d. The downward movement of guide tabs 78 d in side channels 142 has the optional effect of further compressing drive spring 92 d.

As the lever 132 is continued to be depressed into main body 20 d, guide tabs 78 d eventually clear corners 146 and disengage from side channels 142. At this point, guide tabs 78 d align with main channel 140 of guide channels 138 and are free to move forward therein under the biasing force of drive spring 92 d. Correspondingly, with the engagement between guide tabs 78 d and corners 146 released, the drive spring 92 d is free to bias lancet 70 d to the puncturing position. With the stored potential energy in drive spring 92 d released, drive spring 92 d thereafter biases the lancet 70 d away from rear cap 24 d and through main body 20 d. During such propelling movement, the engagement of guide tabs 78 d in guide channels 138 guides lancet 70 d axially through main body 20 d. The distal biasing energy imparted to lancet 70 d is preferably sufficient to cause the puncturing end 74 d of lancet 72 d to project a sufficient distance and with sufficient force from the front opening 30 d in main body 20 d to cause a puncture wound in the desired location on the patient's body. Moreover, during the propelling movement of lancet 70 d, proximal spring guide 86 d on carrier body 76 d releases from drive spring 92 d which remains connected to rear cap 24 d. The engagement of posts 150 with stops 144 in guide channels 138 prevents lancet 70 d from axial movement entirely out of main body 20 d through front opening 30 d.

As the lancet 70 d moves forward in the propelling movement, distal spring guide 88 d engages retraction spring 94 d. The biasing force of drive spring 92 d is at least in part applied to retraction spring 94 d by engagement of distal spring guide 88 d with retraction spring 94 d, which causes the retraction spring 94 d to compress toward distal end pocket 98 d. The retraction spring 94 d permits puncturing end 74 d of lancet 72 d to extend through front opening 30 d in main body 20 d a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow, and thereafter return lancet 70 d to a generally fixed and stationary position within housing 12 d. In particular, as the retraction spring 94 d returns to a relaxed or unloaded state within main body 20 d, the lancet 70 d is retracted in main body 20 d and returned to a generally fixed and stationary position within main body 20 d. Thereafter, the engagement of retraction spring 94 d with distal spring guide 88 d maintains the positioning of lancet 70 d within main body 20 d with puncturing end 74 d of lancet 72 d shielded within housing 12 d, and prevents further movement of lancet 70 d to the puncturing position.

Referring to FIGS. 24-30, a fifth embodiment of a lancet device 10 e is generally illustrated, and comprises the same basic components or elements as lancet devices 10 a-c described previously. Generally, lancet device 10 e comprises a housing 12 e, a shield 14 e movably associated with the housing 12 e, and a lancet 70 e movably disposed in housing 12 e. As the basic components of lancet device 10 e are substantially similar to the corresponding components of lancet devices 10 a-c discussed previously, only distinct differences between these general components will be discussed herein, along with the use and sequence of operation of lancet device 10 e.

The sequence of operation of lancet device 10 e generally follows the sequence of operation of lancet devices 10 a-c, wherein lancet device 10 e is armed and actuated through the retraction (i.e., depression) of shield 14 e into housing 12 e. Generally, in lancet device 10 e, arming and actuation of lancet device 10 e occurs as a result of proximal or rearward end 54 e of shield body 50 e of shield 14 e engaging a structure within housing 12 e that causes compression (i.e., loading) of drive spring 92 e and, upon release of such compression, drive spring 92 e biases lancet 70 e through a propelling movement resulting in puncturing end 74 e of lancet 72 e projecting from shield 14 e for puncturing procedure the skin of a patient, as discussed in more detail herein.

In lancet device 10 e, shield 14 e comprises a shield body 50 e with a rear ledge or rim 162 at shield proximal end 54 e. The rear ledge or rim 162 is generally adapted for contact or engagement with a slide plate 164 disposed in housing 12 e to cause actuation of lancet device 10 e as described in detail herein. Slide plate 164 forms the structure for compressing drive spring 92 e alluded to previously. Rear ledge or rim 162 is also adapted to engage forward rim 42 e of main body 20 e of housing 12 e to prevent shield body 50 e from axially sliding completely out of housing 12 e through front opening 30 e defined in the forward end wall 58 e of shield body 50 e. Rear rim 162 is sized such that it may slide along the inner surface of main body 20 b when shield body 50 e is retracted (i.e., depressed) into main body 20 e, as will occur when the lancet device 10 b is actuated by a user.

Slide plate 164 forms the internal structure in main body 20 e of housing 12 e which is used to cause compression of drive spring 92 e thereby storing potential energy in drive spring 92 e which, upon release, is used to bias lancet 70 e to the puncturing position. Slide plate 164 is disposed in main body 20 e of housing 12 e to be in contact with rear rim 162 of shield body 50 e. Slide plate 164 is associated with rear rim 162 of shield body 50 e so that slide plate 164 may move rearward with shield body 50 e as shield body 50 e is retracted (i.e., depressed) into main body 20 e of housing 12 e to arm and actuate lancet device 10 e. Slide plate 164 defines a generally centrally-located keyhole or key opening 166 that is sized and shaped to generally conform to the transverse cross-sectional shape of carrier body 76 e of lancet 70 e, to allow the cross-section of carrier body 76 e to pass therethrough during actuation of lancet device 10 e. In particular, keyhole 166 comprises a central, typically circular-shaped portion 168 and two contiguous laterally-extending notches 170, which define a shape that permits the transverse cross-section of carrier body 76 e to pass therethrough during actuation of lancet device 10 e, as discussed further herein.

A further difference in lancet device 10 e when compared to lancet devices 10 a-c discussed previously lies in the formation of rear cap 24 e, and the interaction therewith by slide plate 164 and shield body 50 e to cause arming and actuation of lancet device 10 e. As in previous embodiments, rear cap 24 e comprises an annular rim 36 e that engages an annular rear rim 32 e of main body 20 e of housing 12 e. In particular, annular lip 38 e on annular rim 36 e engages annular groove 34 e defined in annular rim 32 e to join rear cap 24 e to main body 20 e. However, in lancet device 10 e, annular rim 36 e is elongated and extends distally a greater distance into main body 20 e of housing 12 e, so as to be positioned proximate to the rear rim 162 of shield body 50 e in the initial state of lancet device 10 e. Annular rim 36 e defines a tapered internal cam surface 172, which is shaped to impart a specific cam motion to slide plate 164 due to contact therewith and ultimately cause arming and actuation of lancet device 10 e as described hereinafter.

In the initial state of lancet device 10 e, drive spring 92 e is associated with lancet 70 e, with the drive spring 92 e extending from the inner side of rear cap 24 e to carrier body 76 e. In lancet device 10 e, carrier body 76 e is further formed with a proximal or rear rim 174 at the rearward end thereof. Rim 174 generally defines the forward end of proximal spring guide 86 e and typically has a diameter larger than the diameter of distal spring guide 88 e and typically at least equal to the diameter of the forward end of drive spring 92 e. Rim 174 defines a contact structure or surface on carrier body 76 e that is used to compress drive spring 92 e to place the lancet device 10 e into a loaded or armed state. Once the drive spring 92 e is released, thereby releasing the potential energy stored therein during the compression of drive spring 92 e, the drive spring 92 e will act against rear rim 174 to bias lancet 70 e to the puncturing position. Guide tabs 78 e are typically formed integrally with rear rim 174 and extend laterally therefrom.

With the various distinguishing components of lancet device 10 e now set forth, use and operation of lancet device 10 e will now be described with continued reference to FIGS. 24-30. Prior to use, cover 100 e extending distally from carrier body 76 e is removed by breaking the frangible connection with carrier body 76 e, and withdrawing cover 100 e from forward opening 60 e in forward end wall 58 e of shield body 50 e in the manner described previously. The forward end wall 58 e of shield body 50 e may then be placed in contact with a target location on a patient's body. In the initial, unarmed state of lancet device 10 e, the drive spring 92 e is substantially uncompressed (i.e., unloaded) and extends from rear rim 174 on carrier body 76 e to rear cap 24 e. In the initial, unarmed state of lancet device 10 e, drive spring 92 e is in a relaxed condition and acts on rear rim 174 on carrier body 76 e to position lancet 70 e at a generally fixed and stationary position within main body 20 e of housing 12 e, wherein the lancet 70 e occupies a substantially fixed position relative to main body 20 e and shield body 50 e. Additionally, the drive spring 92 e acting on rear rim 174 causes the carrier body 76 e to engage (i.e., contact) the rear side of slide plate 164. In particular, drive spring 92 e in its relaxed or unloaded initial state, causes the front side or surface of rear rim 174 and front surface 82 e of guide tabs 78 e to be in substantial contact with the rear side or surface of slide plate 164. Moreover, in the initial state of lancet device 10 e, slide plate 164 is positioned in contact with the rear rim 162 of shield body 50 e so that rear rim 174 and guide tabs 78 e of carrier body 76 e are offset vertically from the keyhole 166 defined in slide plate 164. Accordingly, in the initial state of lancet device 10 e, rear rim 174 and guide tabs 78 e are in interference engagement with the rear side of slide plate 164.

To use the lancet device 10 e, the user grasps opposing sides of housing 12 e and exerts downwardly directed force on main body 20 e thereof in the direction of Arrow X. This force causes an opposing force on forward end wall 58 e of shield body 50 e, causing shield body 50 e to retract (i.e., depress) axially within main body 20 e. As shield body 50 e retracts into main body 20 e, rearward end 54 e of shield body 50 e moves proximally (i.e., rearward) toward rear cap 24 e. In particular, rear rim 162 at the rearward end 54 e of shield body 50 e moves rearward while simultaneously interacting with cam surface 172. Further, as rear rim 162 of shield body 50 e moves rearwardly in main body 20 e, slide plate 164 also begins to move rearwardly in combination with the rear rim 162 toward rear cap 24 e, due to the engagement between slide plate 164 and rear rim 162. Additionally, lancet 70 e will move rearward with shield body 50 e and slide plate 164 due to the offset interference engagement between rear rim 174 and guide tabs 78 e and slide plate 164. The rearward movement of lancet 70 e will further begin to compress drive spring 92 e, due to the engagement of drive spring 92 e with the rear side of rear rim 174 on carrier body 76 e.

The downward movement imparted to housing 12 e also causes the slide plate 164 to interact with tapered cam surface 172 defined by annular rim 36 e of rear cap 24 e. Due to the tapered shape of cam surface 172 from the forward or distal end of annular rim 36 e toward the Central Axis A of lancet device 10 e, slide plate 164 moves downward in internal cavity 28 e of main body 20 e as the slide plate 164 is retracted in main body 20 e. Accordingly, as shield body 50 e is retracted (i.e., depressed) into main body 20 e of housing 12 e, slide plate 164 moves rearwardly and downward in main body 20 e, and this combined movement occurs substantially simultaneously. Additionally, continued rearward movement of shield body 50 e has the effect of compressing the drive spring 92 e and storing the potential energy necessary to bias the lancet 70 e to the puncturing position.

Once the slide plate 164 moves downward to a position where the transverse cross-sectional shape of the carrier body 76 e defined at the location of rear rim 174 and guide tabs 78 e on carrier body 76 e matches the corresponding profile of keyhole 166, the interfering engagement restraining the drive spring 92 e is removed and the potential energy stored in drive spring 92 e is released. With the stored potential in drive spring 92 e released and providing a biasing force acting on lancet 70 e, the drive spring 92 e biases the lancet 70 e away from rear cap 24 b and through shield body 50 e. During such propelling movement, the corresponding guide tabs 78 e and guide channels 80 b guide lancet 70 b axially through shield body 50 e. The biasing force acting on lancet 70 e is preferably sufficient to cause the puncturing end 74 e of lancet 72 e to project a sufficient distance and with sufficient force from the forward opening 60 e in shield body 50 e to cause a puncture wound at the target location on the patient's body. Moreover, during the propelling movement of lancet 70 e, proximal spring guide 86 e on carrier body 76 e releases from drive spring 92 e which remains connected to rear cap 24 e.

As the lancet 70 e moves forward in the propelling movement, distal spring guide 88 e engages retraction spring 94 e. The biasing/propelling force provided by drive spring 92 e is at least in part applied to retraction spring 94 e by engagement of distal spring guide 88 e with retraction spring 94 e, which causes the retraction spring 94 e to compress toward distal end pocket 98 e. The retraction spring 94 e permits puncturing end 74 e of lancet 72 e to extend through forward opening 60 e in shield body 50 e a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow, and thereafter returns lancet 70 e to a substantially fixed and stationary position within shield 14 e. Distal spring guide 88 e provides an abutment surface for engaging internal sleeve 96 e in shield body 50 e supporting retraction spring 94 e to prevent lancet 70 e from axial movement entirely out of shield body 50 e through forward opening 60 e. As the retraction spring 94 e returns to a relaxed or unloaded state within shield body 50 e, the lancet 70 e is retracted in shield 14 e and returned to a substantially fixed and stationary positioned within shield body 14 e. Thereafter, the engagement of retraction spring 94 e with distal spring guide 88 e maintains the lancet 70 e at a generally fixed position within shield body 50 e. This engagement further maintains puncturing end 74 e shielded within shield body 50 e, and prevents further movement of lancet 70 e to the puncturing position.

Referring to FIGS. 31-37, a sixth embodiment of a lancet device 10 f is generally illustrated, and generally comprises a housing 12 f and a lancet 70 f disposed in housing 12 f. Lancet device 10 f is similar in structure to lancet device 10 d discussed previously but includes a plate for actuating the device in a similar manner to lancet device 10 e discussed immediately above. As with lancet device 10 d, lancet device 10 f is not actuated through the retraction (i.e., depression) of a shield element into housing 12 f, and is initially provided in an armed or loaded state, with lancet 70 f ready to be biased to the puncturing position by drive spring 92 f upon release of an interfering structure. The interfering structure in lancet device 10 f is a plate similar that described previously and additional details of which specific to the present embodiment will be provided herein.

In the initial, armed state of lancet device 10 f, drive spring 92 f is in a compressed (i.e., loaded) state, ready to bias the lancet 70 f through a puncturing procedure upon release. As the configuration of the housing 12 f, lancet 70 f, and drive spring 92 f are generally similar to lancet device 10 d discussed previously, the following discussion will build upon the previously discussed structure of lancet device 10 d.

Housing 12 f of lancet device 10 f comprises an elongated main body 20 f that generally defines a cylindrical and hollow configuration. The main body 20 f has a distal or forward end portion 22 f, and a rear cap 24 f forming a proximal or rearward end portion 26 f of the main body 20 f. The interior of housing 12 f is generally open and comprises an internal cavity 28 f. The internal cavity 28 f is closed at the rearward end due to rear cap 24 f, and includes a front opening 30 f defined in forward end portion 22 f of main body 20 f, and through which lancet 70 f extends when lancet device 10 f is actuated. Main body 20 f and rear cap 24 f may be integrally formed. Typically, main body 20 f and rear cap 24 f are separate elements that are affixed together to form housing 12 f, in the manner described previously, but may also be integral also in the manner described.

In lancet device 10 f, distal or forward end portion 22 f of main body 20 d comprises an axially rearward-extending internal sleeve 96 f which defines a distal end pocket 98 f for receiving and supporting retraction spring 94 f. Forward rim 42 f at the forward end portion 22 f of main body 20 f is adapted to be placed in contact with a patient's body during use of lancet device 10 f. Additionally, main body 20 f comprises an actuation structure or actuator 180 for causing actuation of lancet 70 f and corresponding release of compressed drive spring 92 f. Actuator 180 generally comprises an actuating button or lever 182 that is pivotally associated with main body 20 f. The pivotal association with main body 20 f may be in the form of a living hinge 183 or equivalent structure and lever 182 may thus be integrally formed with main body 20 f. Actuator 180 further comprises a plate member 184, which depends from an inner side of actuating lever 182 and extends downward into internal cavity 28 f of main body 20 f of housing 12 f. Plate member 184 is oriented substantially transverse to the Central Axis A of main body 20 f in the initial state of actuating lever 182. Plate member 184 may be formed integrally with lever 182 or be provided as a separate component from lever 182 and be joined thereto. For example, lever 182 may define a recess 186 that accepts a tab 188 extending from plate member 184 to connect plate member 184 to lever 182. Tab 188 may be secured in recess 186 via friction fit and/or with an adhesive. The pivotal connection be lever 182 and main body 20 f is provided so that plate member 184 may interact with lancet 70 f and, further, drive spring 92 f to release the compressed drive spring 92 f and cause actuation of lancet device 10 f.

Main body 20 f of housing 12 f comprises opposing inner sidewalls 190 each defining an internal guide channel 192 for guiding movement of lancet 70 f within main body 20 f. Guide channels 192 may be formed as longitudinally extending grooves or recesses in the inner sidewalls 190, or may be formed as part of a raised structure extending inward from sidewalls 190. The guide channels 192 are adapted to receive to receive guide tabs 78 f on carrier body 76 f to guide movement of lancet 70 f within main body 20 f. Guide channels 190 each define an end surface or stop 194, which may be use to provide a stop for guide tabs 78 f to prevent lancet 70 f from axial movement entirely out of main body 20 f through front opening 30 f after the lancet device 10 f is actuated. However, desirably distal spring guide 88 f may be formed to provide an abutment surface for engaging internal sleeve 96 f in shield body 50 f supporting retraction spring 94 f to prevent lancet 70 f from axial movement entirely out of shield body 50 f through forward opening 60 f.

Lancet 70 f is formed in a generally analogous manner to lancet 70 d of lancet device 10 d discussed previously, with carrier body 76 f including two outward extending guides tabs 76 f and supporting a lancet 72 f with a puncturing end 74 f at the forward end thereof. As in previous embodiments, guide tabs 78 f extending laterally outward from carrier body 76 f engage guide channels 190 in main body 20 f. Carrier body 76 f further comprises a proximal or rear rim 196 at the rearward end thereof. Rim 196 generally defines the forward end of proximal spring guide 86 f and typically has a diameter larger than the diameter of distal spring guide 88 f on carrier body 76 f, and typically at least equal to the diameter of the forward end of drive spring 92 f. Rim 196 is provided as a contact structure or surface on lancet 70 f for interference engagement with plate member 184 to prevent actuation of lancet device 10 f, and maintain compression of drive spring 92 f in the initial, pre-actuated state of lancet device 10 f. As indicated, the diameter of rim 196 is also typically sized to be at least equal to the diameter of drive spring 92 f and provides a contact structure or surface that maintains drive spring 92 f in a compressed state in the initial, pre-actuated state of lancet device 10 f. During actuation of lancet device 10 f, drive spring 92 f will act against rim 196 to bias lancet 70 f to the puncturing position, as described further herein. In general, lancet 70 f is adapted for axial movement through the internal cavity 28 f of main body 20 f between an initial position wherein plate member 184 is in interference engagement with the lancet 70 f, thereby holding or maintaining drive spring 92 f in a compressed or loaded state, to a puncturing position where the puncturing end 74 f of lancet 72 f extends beyond the front opening 30 f in main body 20 f a sufficient amount to cause a puncture wound on a patient's body.

Plate member 184 defines a generally centrally-located keyhole or key opening 197 that is sized and shaped to match the transverse cross-sectional shape or outline of carrier body 76 f of lancet 70 f to allow the carrier body 76 f to pass therethrough during actuation of lancet device 10 f. In particular, keyhole 197 comprises a central, typically circular-shaped portion 198 and two contiguous laterally extending notches 200 which define a shape that permits the carrier body 76 f to pass therethrough during actuation of lancet device 10 f.

With the general components of lancet device 10 f now set forth, use and operation of lancet device 10 f will now be described with continued reference to FIGS. 31-37. Prior to use, cover 100 f extending distally from carrier body 76 f is removed by breaking the frangible connection with carrier body 76 f, and withdrawing cover 100 f from the front opening 30 f in main body 20 f in the manner described previously. In the initial, pre-actuated state of lancet device 10 f, plate member 184 is positioned relative to carrier body 76 f such that the rear rim 196 and guide tabs 78 f on carrier body 76 f are offset from keyhole 197 and, therefore, in interference engagement with the rear side of plate member 184. In particular, the transverse cross-sectional shape defined by the carrier body 76 f at the location of rear rim 196 and guide tabs 78 f is offset, typically vertically offset, from keyhole 197. As a result, drive spring 92 f is held in a compressed, loaded state between rear rim 196 on carrier body 76 f and rear cap 24 f. The rearward or proximal end of drive spring 92 f may be secured to rear cap 24 f in the manner discussed previously in this disclosure. The forward or distal end of drive spring 92 f may be associated with the proximal spring guide 86 f and rear rim 196 of carrier body 76 f in the manner described previously, and may be secured to rear rim 196 by suitable means such as by adhesive and/or direct mechanical attachment.

To carry out a puncturing procedure, the user grasps opposing sides of housing 12 f and places the forward rim 42 f of main body 20 f in contact with a target location on a patient's body. The user then exerts downward pressure in the direction of Arrow X on lever 182, causing lever 182 to pivot (i.e., depress) into internal cavity 28 f of main body 20 f. As lever 182 pivots downward in internal cavity 28 f, plate member 184 also moves downward in internal cavity 28 f while initially maintaining an interference engagement with lancet 70 f and thereby continuing to maintain the drive spring 92 f in a compressed state. In particular, plate member 184 initially maintains an interference engagement with lancet 70 f, wherein the forward side or surface of rear rim 196 and forward side or surface of guide tabs 78 f on carrier body 76 f are in interference engagement with the rearward side or surface of plate member 184 thereby maintaining the drive spring 92 f compressed between rear rim 196 and rear cap 24 a. As the lever 182 is continued to be depressed into main body 20 a, keyhole 197 in plate member 184 eventually aligns with a matching transverse cross-sectional shape defined by carrier body 76 f at the location of the rear rim 196 and guide tabs 78 f, thereby permitting the carrier body 76 f to pass through keyhole 197. As the interference engagement between the rear rim 196 and guide tabs 78 f and plate member 184 is released, the stored potential energy in drive spring 92 e is also released and used to move the lancet 70 f to the puncturing position.

As shown in FIGS. 35-37, the pivotal movement of lever 182 results in a corresponding pivotal movement by plate member 184. As a result, as plate member 184 is pivoted downward into main body 20 f, the plate member 184 begins to define an angle α with an axis perpendicular PA to the Central Axis A of lancet device 10 f and housing 12 f in particular. As the lever 182 is further depressed into main body 20 f, the angle formed by plate member increases to angle α′. The angular orientation of plate member 184 causes keyhole 197 to be at a slight angular orientation relative to Central Axis A. As a result, as plate member 184 moves downward and slightly forward in main body 20 f, keyhole 197 does not align exactly along Axis PA but at an angle to this axis. Due to the angular “offset” between keyhole 197 and the Central Axis A of main body 20 f, the matching transverse cross-sectional shape defined by carrier body 76 f at the location of the rear rim 196 and guide tabs 78 f will not pass easily through keyhole 197 unless the size of keyhole 197 is increased to compensate for the angular orientation of plate member 184. Therefore, in lancet device 10 f it is desirable to increase the size of keyhole 197 to compensate for the forward angular movement of plate member 184. Alternatively, plate member 184 could be positioned in a track such that pivotal movement of lever 182 translates into linearly tracked movement of plate member 184. Plate member 184 would still allow for providing clearance for rear rim 196 and guide tabs 78 f to pass through keyhole 197.

With the stored potential in drive spring 92 f released and providing a biasing force acting on lancet 70 f, the drive spring 92 f biases the lancet 70 f away from rear cap 24 f and through main body 20 f. During such propelling movement, the engagement of guide tabs 78 f in guide channels 192 guides lancet 70 f axially through main body 20 f. The biasing force applied to lancet 70 f is preferably sufficient to cause the puncturing end 74 f of lancet 72 f to project a sufficient distance and with sufficient force from the front opening 30 f in main body 20 f to cause a puncture wound in the desired location on the patient's body. Moreover, during the propelling movement of lancet 70 f, proximal spring guide 86 f on carrier body 76 f releases from drive spring 92 f which remains connected to rear cap 24 f. As the lancet 70 f moves forward in the propelling movement, distal spring guide 88 f engages retraction spring 94 f. The biasing/propelling force of drive spring 92 f is at least in part applied to retraction spring 94 f by engagement of distal spring guide 88 f with retraction spring 94 f, which causes the retraction spring 94 f to compress toward distal end pocket 98 f. The retraction spring 94 f is adapted to permit puncturing end 74 f of lancet 72 f to extend through front opening 30 f in main body 20 f a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow, and thereafter return lancet 70 f to a substantially fixed and stationary position within housing 12 f. As indicated, distal spring guide 88 f desirably provides an abutment surface for engaging internal sleeve 96 f supporting retraction spring 94 f to prevent lancet 70 f from axial movement entirely out of main body 20 f of housing 12 f through front opening 30 f. As the retraction spring 94 f returns to a relaxed or unloaded state within main body 20 f, the lancet 70 f is retracted in main body 20 f and returned to a substantially fixed and stationary positioned within main body 20 f. Thereafter, the engagement of retraction spring 94 f with distal spring guide 88 f maintains the lancet 70 f within main body 20 f, with the puncturing end 74 f of lancet 72 f shielded within housing 12 f and preventing further movement of lancet 70 f to the puncturing position.

Referring to FIGS. 38-43, a seventh embodiment of a lancet device 10 g is shown and which is a variation of lancet device 10 f described immediately previously. Lancet device 10 g is similar in all respects to lancet device 10 f described immediately above, except for comprising a different configuration of actuation structure or actuator 180 g, which will now be detailed. Actuator 180 g of lancet device 10 g replaces the pivoting lever 182 of actuator 180 of lancet device 10 f with a depressible button 182 g, which allows plate member 184 g to be depressed into main body 20 g directly along Axis PA, such that plate member 184 g no longer pivots into main body 20 g and thereby form an angle with Axis PA, as was the case with the lever 182 and depending plate member 184 of actuator 180 in lancet device 10 f. Other than the foregoing difference between actuator 180 g of lancet device 10 g and actuator 180 of lancet device 10 f, all other aspects of lancet device 10 g are identical to lancet device 10 f described previously.

As further shown in the FIGS. 31-43 associated with lancet devices 10 f, 10 g, actuation structures or actuators 180, 180 g of these devices comprise a structure for engaging main bodies 20 f, 20 g of housing 12 f, 12 g such that, once actuation structures or actuators 180, 180 g are depressed, the actuators 180, 180 g are prevented from returning to their initial positions. In actuators 180, 180 g, one or more detents 202, 202 g are provided on a proximal or rearward end of lever 182 and a proximal or rearward end of button 182 g, respectively. Detents 202, 202 g are adapted to engage in a snap-fit or friction-fit manner with a mating recess 204 defined in main bodies 20 f, 20 g. Recesses 204, 204 g in main bodies 20 f, 20 g are provided opposite to the proximal or rearward end of lever 182 and the proximal or rearward side of button 182 g, respectively. In operation, as lever 182 and button 182 g are depressed into main bodies 20 f, 20 g, respectively, detents 202, 202 g successively engage the mating recesses 204, 204 g in main bodies 20 f, 20 g. The mating engagement of detents 202, 202 g in mating recesses 204, 204 g prevents lever 182 and button 182 g from returning to their initial positions. The use of multiple detents 202, 202 g allows lever 182 and button 182 g to be moved in discrete downward steps or stages to the actuating position, where keyholes 196, 196 g defined in plate members 184, 184 g align with the matching or corresponding transverse cross-sectional shape of carrier bodies 76 f, 76 g to permit lancets 70 f, 70 g to move to the puncturing position.

Referring to FIGS. 44-52, an eighth embodiment of a lancet device 10 h is generally illustrated, and generally comprises a housing 12 h and a lancet 70 h disposed in housing 12 h. Lancet device 10 h differs from lancet devices 10 a-c, e discussed previously, as lancet device 10 h is not actuated through the retraction (i.e., depression) of a shield element into housing 12 h. However, lancet device 10 h is similar to lancet devices 10 d, 10 f, and 10 g discussed previously because lancet device 10 h is initially provided in an armed or loaded state, with lancet 70 h ready to be biased to the puncturing position by drive spring 92 h upon release or removal of an interfering engagement or structure, and likewise comprises a depressible actuation structure or actuator for releasing or removing the interference engagement. Additionally, lancet device 10 h incorporates a cutting and shearing concept such as that utilized in lancet devices 10 a, 10 b to remove the interference engagement. As in previous embodiments, in the initial armed state of lancet device 10 h, drive spring 92 h is in a compressed (i.e., loaded) state, ready to bias the lancet 70 h to a puncturing position in skin-puncturing operation upon removal of an interference engagement.

Housing 12 h of lancet device 10 h comprises an elongated main body 20 h that generally has a cylindrical and hollow configuration. The main body 20 h has a distal or forward end portion 22 h, and a rear cap 24 h forming a proximal or rearward end portion 26 h of the main body 20 h. The interior of main body 20 h is generally open and defines an internal cavity 28 h. The internal cavity 28 h is closed at the rearward end due to the presence of rear cap 24 h and includes a front opening 30 h defined in forward end portion 22 h of main body 20 h, and through which lancet 70 h extends when lancet device 10 h is actuated. Main body 20 h and rear cap 24 h may be integrally formed. Typically, main body 20 h and rear cap 24 h are separate elements that are affixed together to form housing 12 h, as illustrated, which facilitates assembly of lancet device 10 h. As examples, main body 20 h and rear cap 24 h may be affixed together through an appropriate medical grade adhesive, and/or may connected using inter-engaging structures providing a mechanical engagement therebetween, such as a friction-fit or a snap-fit construction. For example, main body 20 h may comprise an annular rim 32 h that cooperates with an annular rim 36 h on rear cap 24 h and which is recessed to accept annular rim 32 h. An adhesive, such as a medical grade adhesive, may be used to secure annular rim 32 h with annular rim 36 h. As with lancet devices 10 d, 10 f, and 10 g, distal or forward end portion 22 h of main body 20 h comprises an axially rearward-extending sleeve 96 h which defines a distal end pocket 98 h for receiving and supporting retraction spring 94 h.

Additionally, main body 20 h of housing 12 h further comprises a pivoting actuation structure or actuator 206 in a generally analogous manner to lancet device 10 d described previously, for causing actuation of lancet 70 h and corresponding release of drive spring 92 h. Actuation structure or actuator 206 generally comprises an actuating lever 208 that is pivotally movable relative to main body 20 h, and is desirably located at the rear end portion 26 h of main body 20 h proximate to rear cap 24 h. Actuating lever 208 may extend distally or forward from rear cap 24 h and be connected to rear cap 24 h by a living hinge or equivalent structure. Lever 208 may thus be integrally formed with rear cap 24 h. The lever 208 may alternatively be associated with main body 20 h. For example, lever 208 may be formed as part of the rear end portion 26 h of main body 20 h, or even formed as part of the forward end portion 22 h of main body 20 h and extend rearward or proximally toward rear cap 24 h. In contrast to previous embodiments, lever 208 comprises two opposed and depending sidewalls 210. Sidewalls 210 terminate with a cutting edge or blade 212. Cutting edge 212 may be an integral, sharp edge on sidewalls 210 or be provided as a separate cutting blade secured to the ends of sidewalls 210. Lever 208 is generally adapted to be depressed into the internal cavity 28 h of main body 20 h so that cutting edges 212 may cut or sever an interfering engagement within in main body 20 h restraining drive spring 92 h, and thereby cause actuation of lancet device 10 h as described in detail herein.

Main body 20 h of housing 12 h may be formed with a generally rectangular cross-section as illustrated in FIG. 46 and comprise opposing inner sidewalls 213 each defining an internal shelf or ledge 214. Lancet 70 h is generally adapted to engage shelves 214 for restraining compressed drive spring 92 h and, upon depression of lever 208 into main body 20 h, a structure on lancet 70 h is cut or severed to release the interference engagement of lancet 70 h with shelves 214 and, thus, release the biasing force of drive spring 92 h. Main body 20 h defines a main guide channel 216 that accommodates lancet 70 h and guides movement of lancet 70 h within main body 20 h.

Lancet 70 h is formed in a generally analogous manner as previous embodiments and comprises a lancet 72 h with a puncturing end 74 h at the forward end thereof, and a carrier body 76 h supporting lancet 72 h at the rearward end thereof. The carrier body 76 h now comprises a pair of outward extending tab members 218 which generally take the place of the guide tabs discussed previously in this disclosure. Tab members 218 are adapted for interference engagement with shelves 214 for positioning lancet 70 h in housing 12 h and main body 20 h in particular. The interference engagement between tab members 218 and shelves 216 further serves to restrain compressed drive spring 92 h. Tab members 218 are adapted to be cut or severed by cutting edge 212 on sidewalls 210 upon depression of lever 208 into main body 20 h. For this purpose, tab members 218 may define a tapered cross-section forming a narrow neck or weakened area 220 which may be cut through by cutting edge 212 on sidewalls 210. Neck area 220 may take other forms, such as a score line, but is generally adapted to be easily cut or sheared through (i.e., cause failure of) by cutting edge 212 when lever 208 is depressed into main body 20 h of housing 12 h. Carrier body 76 h further comprises a proximal or rearward end spring guide 86 h and a distal or forward end spring guide 88 h for engaging drive spring 92 h and retraction spring 96 h, respectively, of lancet device 10 h. Spring guides 86 h, 88 h may be formed integral with the body of carrier body 76 h or be provided as distinct, separate elements and secured to the body of carrier body 76 h in the manner described previously.

In operation, lancet 70 h is adapted for axial movement through the main guide channel 216 of main body 20 h between an initial position wherein tab members 218 are in interference engagement with shelves 214 defined by main body 20 h and the puncturing end 74 h of lancet 72 h is disposed entirely within main body 20 d, to a puncturing position wherein carrier body 76 h is disposed in main guide channel 216 with the puncturing end 74 h extending beyond front opening 30 h of main body 20 h a sufficient distance to cause a puncture wound in a patient's body. In the initial, pre-actuated state of lancet device 10 h, drive spring 92 h is at least partially compressed between rear cap 24 h and carrier body 76 h and typically has sufficient stored potential energy to conduct a skin-piercing procedure. The rearward or proximal end of drive spring 92 h is typically secured to rear cap 24 h in the manner discussed previously in this disclosure. The forward or distal end of drive spring 92 h is associated with carrier body 76 h and disposed about proximal spring guide 86 h, and may be secured to carrier body 76 h by similar means discussed previously, as by suitable adhesive or direct mechanical attachment. As shown, for example, in FIG. 47, drive spring 92 h directly engages carrier body 76 h, and the carrier body 76 h may further comprise two outward-extending tabs or flanges 222 against which the forward end of drive spring 92 h is engaged to provide additional surfaces for transmitting the biasing force of drive spring 92 h to lancet 70 h to move the lancet 70 h to the puncturing position.

With continued reference to FIGS. 44-52, use and operation of lancet device 10 h will now be discussed. As with previous embodiments, a cover (not shown) extending distally from carrier body 76 h may be provided with carrier body 76 h. As with previous embodiments, such a cover would be removed by breaking the frangible connection with carrier body 76 h and withdrawing the cover from front opening 30 h in main body 20 h. Forward end rim 42 h of main body 20 h may then be placed in contact with the target location on the patient's body. As indicated previously, lancet device 10 h is initially provided in an armed state, with lancet 70 h ready to initiate a puncturing procedure when compressed drive spring 92 h is released.

To carry out a puncturing procedure, the user grasps opposing sides of housing 12 h and exerts downwardly directed force in the direction of Arrow X on lever 208, causing lever 208 to pivot (i.e., depress) into internal cavity 28 h of main body 20 h. As lever 208 is depressed into main body 20 h, depending sidewalls 210 and, more particularly, cutting edge 212 at the end of each depending sidewall 210 contacts tab members 218 at the reduced cross-sectional, weakened area 220 on tab members 218. As the lever 208 is continued to be depressed into main body 20 h, cutting edge 212 on sidewalls 210 begins to cut through the neck area 220 on each tab member 218. Once the tab members 218 are completely cut-through, the interference engagement between tab members 218 and shelves 214 defined by sidewalls 213 of main body 20 h is removed, releasing the drive spring 92 b to bias lancet 70 h to the puncturing position. With the biasing force of drive spring 92 h released, drive spring 92 h thereafter biases the lancet 70 h away from rear cap 24 h and through main guide channel 216. The biasing force imparted to lancet 70 h is preferably sufficient to cause the puncturing end 74 h of lancet 72 h to project a sufficient distance and with sufficient force from the front opening 30 h in main body 20 h to cause a puncture wound in the desired location on the patient's body. Moreover, during the propelling movement of lancet 70 h, proximal spring guide 86 h on carrier body 76 h releases from drive spring 92 h which remains connected to rear cap 24 h.

As the lancet 70 h moves forward in the propelling movement, distal spring guide 88 h engages retraction spring 94 h. The biasing/propelling force provided by drive spring 92 h is at least in part applied to retraction spring 94 h by engagement of distal spring guide 88 h with retraction spring 94 h, which causes the retraction spring 94 h to compress toward distal end pocket 98 h. The retraction spring 94 h permits puncturing end 74 h of lancet 72 h to extend through front opening 30 h in main body 20 h a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow, and thereafter return lancet 70 h to a substantially fixed and stationary position within housing 12 h. Carrier body 76 h is desirably formed with a shoulder 224 formed at the base of distal spring guide 88 h, and which is configured to engage an abutment surface or stop 226 defined by sidewalls 213 of main body 20 h in main guide channel 216 to prevent lancet 70 h from axial movement entirely out of main body 20 h through front opening 30 h. The stop 226 is defined rearward of rearward-extending internal sleeve 96 h supporting retraction spring 94 h. As the retraction spring 94 h returns to a relaxed or unloaded state within main body 20 h, the lancet 70 h is retracted in main body 20 h and returned to a substantially fixed and stationary positioned within main body 20 h. Thereafter, the engagement of retraction spring 94 h with distal spring guide 88 h maintains the lancet 70 h shielded within housing 12 h, and prevents further movement of lancet 70 h to the puncturing position, in the manner discussed in detail previously. In this disclosure, various elements have been identified as being adapted to be “cut”, “sheared”, “yielded”, “fractured” to cause release and actuation of lancet device 10. These terms may all be grouped under a common heading of a “failure” item or element which is intended to fail when force is applied thereto in whatever form, for example blunt force or a cutting force.

Referring to FIGS. 53-55, a modification to a lancet device disclosed in U.S. patent application Ser. No. 11/270,330, filed Nov. 30, 2004, and entitled “Contact Activated Lancet Device”, the entire disclosure of which is incorporated herein by reference, is shown. Lancet device 10 disclosed in the foregoing incorporated reference document may include a modified version of a retaining hub 90 i. FIG. 53 shows the retaining hub 90 i as part of the lancet device 10 disclosed in the incorporated reference document, the disclosure of which will be used to describe the location and operation of retaining hub 901. Retaining hub 90 i generally defines an annular shape and is adapted to maintain the lancet 70 in an initial armed position retracted within housing 12. Retaining hub 901 typically includes two opposed and elongated support members 91 i connected by two pivotal cam elements 92 i to form the annular shape of retaining hub 90 i. Cam elements 92 i each include two outward-extending shafts 93 i engaged pivotally with the opposed support members 91 i. Cam elements 92 i each further include at least one typically wedge-shaped contact element 94 i defining an upper contact surface 96 i on the upper surface thereof. Cam elements 92 i each further define a generally centrally located recess or cut-out 100 i defined in a bottom side thereof. The purpose of recess 100 i is described herein in connection with the operation of retaining hub 90 i in lancet device 10. As shown in FIGS. 54 and 55, the cam elements 92 i desirably each include two contact elements 94 i disposed generally at opposite ends of the cam elements 92 i, with the recess 100 i defined in the bottom side of the cam elements 92 i between the contact elements 94 i.

In lancet device 10, retaining hub 901 and lancet 70 are in interference engagement with each other, such that retaining hub 90 i retains the lancet 70 in an initial armed state retracted within housing 12. For example, fingers 82 on carrier element 76 may rest on the upper side of cam elements 92 i, thereby providing interference engagement between the lancet 70 and the retaining hub 90 i. Moreover, upper contact surface 96 i on the contact elements 94 i may be adapted for contacting engagement with structure within housing 12. For example, rear cap 24 of housing 12 may include structure extending therein, such as internal contact 46 integrally formed and extending on at least one, and desirably on two opposing inner sidewalls thereof. As retaining hub 90 i typically includes two contact elements 94 i on each cam element 92 i, two internal contacts 46 may be provided on each of the two opposing inner sidewalls of the housing 12. Each internal contact 46 includes a distal engagement cam surface 47 for contacting engagement with the corresponding contact surface 96 i on contact elements 94 i.

During usual operation of the lancet device 10, axial movement of shield body 50 toward rear cap 24, causes the retaining hub 90 i to be displaced rearwardly toward rear cap 24, with fingers 82 of the carrier element 76 resting upon the cam elements 92 i. Such rearward movement of retaining hub 90 i causes the contact surfaces of engagement cam surfaces 47 of the internal contacts 46 within rear cap 24 to engage and co-act with the corresponding contact surfaces 96 i on the contact elements 94 i of cam elements 92 i. Such engagement and continued downward movement of internal contacts 46 causes the cam elements 92 i to pivot on or rotate about shafts 93 i with respect to support members 91 i. Due to the generally wedge-shaped profile of the contact elements 94 i, the pivotal movement of cam elements 92 i has the effect of further compressing drive spring 102 by further “lifting” fingers 82, at least until the point where rear nub 86 on carrier element 76 contacts the inner side of rear cap 24. At this point, continued axial displacement of shield body 50 toward rear cap 24 pivots cam elements 92 i to a position where recess 100 i defined in the bottom side of cam elements 92 i has rotated to a position generally aligned with fingers 82 at which point the interference engagement between fingers 82 and cam elements 92 i is released by such alignment. The biasing force of drive spring 102 then propels lancet 70 downward away from the rear cap 24 axially through housing 12 and shield body 50, with guide tabs 78 passing axially through the annular opening defined by retaining hub 90 i.

Referring to FIGS. 56-67, a final embodiment of a lancet device 10 k is generally shown. Lancet device 10 k generally includes a housing 12 k, a shield 14 k movably associated with the housing 12 k, and a lancet 70 k movably disposed in housing 12 k. Shield 14 k is movably associated with housing 12 k, and is at least partially disposed within housing 12 k. Shield 14 k extends outward from housing 12 k, while the lancet 70 is contained within housing 12 k and is typically axially movable through the shield 14 k.

Housing 12 k comprises an elongated main body 20 k having a generally cylindrical and hollow configuration. Main body 20 k has a distal or forward end portion 22 k, and a rear cap 24 k forming a proximal or rearward end portion 26 k of the main body 20 k. The interior of main body 20 k is generally open and comprises an internal cavity or bore 28 k. The internal cavity 28 k is closed at the rearward end due to the presence of rear cap 24 k, and includes a front opening 30 k defined by forward end portion 22 k of main body 20 k, and through which shield 14 k extends. Main body 20 k and rear cap 24 k may be integrally formed. Alternatively, main body 20 k and rear cap 24 k may be separate elements that are affixed together to form housing 12 k in the general manner described previously in this disclosure. Main body 20 k further includes a forward rim 42 k formed as part of forward end potion 22 k and which defines front opening 30 k.

Shield 14 k is typically a generally cylindrical, hollow structure comprising a shield body 50 k having a distal or forward end 52 k and a proximal or rearward end 54 k, and defines an internal cavity or bore 56 k extending therethrough. Forward end 52 k of shield body 50 k defines a partial forward end wall or rim 58 k defining a forward opening 60 k, through which a puncturing element of lancet 70 k extends when lancet device 10 k is actuated by a user. Forward end wall 58 k typically defines a small contact area about forward opening 60 k for contacting an intended puncture area on a patient's body. The reduced contact area may be made smaller (i.e., reduced in surface area) by providing a plurality of peripheral indentations (not shown) formed perimetrically in shield 14 k. The external surface features of housing 12 k and shield 14 k may be formed in accordance with the ergonomic features and structure disclosed in application Ser. No. 11/123,849 incorporated by reference previously in this disclosure. Rearward end 54 k of shield body 50 k defines a rear rim 63 k.

Shield 14 k is typically axially and slidably movable within housing 12 k. Shield 14 k and housing 12 k may be coaxially associated, with shield 14 k and housing 12 k coaxially disposed around a common Central Axis A. Shield 14 k and housing 12 k may each be generally cylindrical-shaped. A rotation element or cam follower, typically a guide plate 262 is further associated with shield 14 k. In particular, guide plate 262 is disposed at the rearward end 54 k of shield body 50 k and engages rear rim 63 k of shield body 50 k. Plate 262 is a generally annular-shaped structure and defines a central opening 263 with two opposed clearance slots 264 and two opposed guide slots 266. Clearance slots 264 and guide slots 266 are orientated along axes that are generally orthogonal to one another. An outer periphery or perimeter of plate 262 is formed with two opposed cam guide recesses 268 for receiving and engaging a cam structure adapted to cause rotation of plate 262 to cause actuation of lancet device 10 k as described further herein. Plate 262 is typically in rotational sliding engagement or contact with rear rim 63 of shield body 50 k to permit rotation thereof relative to rear rim 63. In particular, plate 262 comprises a bottom side 270 in contact with rear rim 63 k and an upper side 272 facing away from rear rim 63 k. Due to the contact between the bottom side 270 of plate 262 and rear rim 63, plate 262 is adapted to slide together with shield body 50 k in main body 20 k when axial motion is imparted to shield body 50 k, for example by axially retracting (i.e., depressing) shield body 50 k into main body 20 k to actuate lancet device 10 k as described herein. Accordingly, any axial motion applied to shield body 50 k to retract (i.e., depress) shield body 50 k into main body 20 k of housing 12 k will be transmitted to plate 262 through the contact engagement of rear rim 63 k and plate 262.

Lancet device 10 k further comprises a lancet 70 k disposed within the housing 12 k, and extending into shield 14 k. Lancet 70 k includes a puncturing element shown in the form of a lancet 72 k. Lancet 72 k comprises a puncturing end 74 k at the forward end thereof. Lancet 70 k is generally adapted for axial movement through the internal cavity 56 k of shield body 50 k between an initial position, wherein the puncturing end 74 k is disposed within shield body 50 k, to a puncturing position wherein the puncturing end 74 k extends beyond the forward opening 60 k of shield body 50 k a sufficient distance to cause a puncture wound in a patient's body. The puncturing end 74 k of lancet 72 k is adapted for puncturing the skin of a patient, and may be in the form of a pointed end, needle tip, blade edge, and the like. Puncturing end 74 k may include a preferred alignment orientation, such as with a pointed end or a blade aligned in a specific orientation. In such an orientation, shield body 50 k and/or main body 20 k of housing 12 k may include target indicia corresponding to the alignment orientation of puncturing end 74 k. Indentations (not shown) in the shield body 50 k and/or indentations (not shown) in main body 20 k may function as such an alignment orientation, as described previously in this disclosure.

Lancet 70 k comprises a carrier body 76 k supporting lancet 72 k at the rearward end thereof. Carrier body 76 k and shield body 50 k may include corresponding guiding surfaces for guiding the movement of lancet 70 k in shield body 50 k. For example, carrier body 76 k may include guide tabs 78 k on an external surface thereof, with shield body 50 k defining corresponding guide channels 80 k extending longitudinally along an inner wall thereof for accommodating guide tabs 78 k slidably therein upon actuation of lancet device 10 k. Carrier body 76 k may include a pair of elongated guide tabs 78 k on opposing lateral sides thereof as illustrated, or a single elongated guide tab 78 k, and shield body 50 k may include a corresponding pair of guide channels 80 k extending along opposing inner surfaces thereof corresponding to each of the guide tabs 78 k, or a single corresponding guide channel 80 k. The engagement of guide tabs 78 k in guide channels 80 k in the initial, pre-actuated state of lancet device 10 k ensures that lancet 70 k is prevented from substantial rotation in shield body 50 k during the actuation sequence of lancet device 10 k, wherein plate 262 is set into sliding rotational movement relative to rear rim 63 k as described herein. Upon actuation, engagement of guide tabs 78 k in guide channels 80 k guides movement of lancet 70 k to the puncturing position.

As shown in FIG. 60, in addition to two opposed guide tabs 78 k, carrier body 76 k further comprises two actuation tabs 81 k oriented along an axis generally orthogonal to an axis passing through guide tabs 78 k. Actuation tabs 81 k form part of the actuation structure or actuator of lancet device 10 k. Actuation tabs 81 are shorter in length than guide tabs 78 k, which typically extend approximately the length of carrier body 76 k. Actuation tabs 81 k comprise a distal facing surface 82 k adapted to engage or rest upon the upper side 270 of guide plate 262 in the initial, pre-actuated state of lancet 70 k. Actuation tabs 81 k are generally adapted to mate or align with clearance slots 264 in plate 262 when plate 262 is rotated to the appropriate alignment position with actuation tabs 81 k to allow actuation of lancet device 10 k as described herein. Likewise, guide tabs 78 k are sized to mate with guide slots 266 in plate 262. However, guide tabs 78 k generally extend at least partially through guide slots 266 in the initial, pre-actuated state of lancet device 10 k, and the guide slots 266 are typically sized larger enough to allow plate 262 to rotate relative to carrier body 76 k without guide tabs 78 k interfering with such rotation due to their presence in guide slots 266.

Shield body 50 k may define additional internal guide channels 84 k for receiving actuation tabs 81 k when the interference engagement between actuation tabs 81 k and plate 262 is removed by rotation of plate 262. Such additional guide channels 84 k are optional as the association of guide tabs 78 k and guide channels 84 k is typically sufficient to guide the movement of carrier body 76 k during the puncturing movement of lancet 70 k. If provided, additional guide channels 84 k may extend the internal length of shield body 50 k or along only a portion of the length of shield body 50 k. Carrier body 76 k further comprises a proximal or rearward end spring guide 86 k and a distal or forward end spring guide 88 k for engaging a drive spring and retraction spring, respectively, of lancet device 10 k as described herein. Spring guides 86 k, 88 k may be formed integral with the carrier body 76 k or be provided as distinct, separate elements in the manner described previously in this disclosure.

Movement of the lancet 70 k through the lancet device 10 a is achieved through a biasing force provided by a drive spring 92 k. Drive spring 92 k is adapted to exert a biasing force against lancet 70 k to drive lancet 70 k through lancet device 10 k toward the puncturing position, and is disposed between the rearward end of main body 20 k and the lancet 70 k. Rear cap 24 k may include structure for alignment of and/or for maintaining drive spring 92 k in the proper orientation on rear cap 24 k. For example, rear cap 24 k may include an internal alignment structure (not shown) for correctly positioning the drive spring 92 k. Lancet 70 k, as indicated previously, includes proximal spring guide 86 k which engages the opposite end of drive spring 92 k in the initial or pre-actuated state of lancet device 10 k. Guide tabs 78 k and actuation tabs 81 k may be used as additional or replacement structure for engaging the distal end of drive spring 92 k.

In the initial state of lancet device 10 k, drive spring 92 k is typically in a generally uncompressed, unloaded state between rear cap 24 k and distal spring guide 86 k of carrier body 76 k. However, drive spring 92 k may exert a limited forward biasing or positioning force on carrier body 76 k via proximal spring guide 86 k to help maintain the interference engagement between actuation tabs 81 k and plate 262. Alternatively, drive spring 92 k may be partially compressed between rear cap 24 k and carrier body 76 k and is adapted for further compression therebetween. During actuation of lancet device 10 k, the retraction of shield body 50 k into main body 20 k causes compression or further compression of drive spring 92 k due to the interference engagement between lancet 70 k and plate 262, thereby storing potential energy in drive spring 92 k necessary to bias lancet 70 k to the puncturing position. As shield body 50 k is further retracted into main body 20 k, the rotation of plate 262 relative to lancet 70 k eventually removes the interference engagement between actuation tabs 81 k and plate 262, thereby releasing the potential energy stored in compressed drive spring 92 k as kinetic energy applied to lancet 70 k to bias lancet 70 k to the puncturing position.

A retraction or return spring 94 k may further be provided at the forward end of the lancet device 10 k, for retracting the lancet 70 k within shield body 50 k after lancet 70 k has moved axially to the puncturing position wherein puncturing element 74 k extends outward from the distal or forward end 52 k of shield body 50 k. Retraction spring 94 k is adapted to be engaged by distal spring guide 88 k extending forward from carrier body 76 a during the forward, puncturing movement of lancet 70 k, as described herein. The forward end wall 58 k of shield body 50 k forms a distal end pocket 98 k for receiving and supporting retraction spring 94 k. Retraction spring 94 k is disposed in distal end pocket 98 k throughout the operation sequence of lancet device 10 a in a puncturing procedure. Retraction spring 94 k may be secured to the internal side of the forward end wall 58 k of shield body 50 k through use of a medical grade adhesive or by mechanically securing retraction spring 94 k thereto in the manner described previously in this disclosure. Drive and retraction springs 92 k, 94 k are typically compression springs capable of storing potential energy when in a compressed state. Lancet device 10 k may further include a protective tab or cover 100 k for protectively covering the forward end of the lancet 70 k as described in previous embodiments. The respective elements of the lancet device 10 k are all typically formed of molded plastic material, such as a medical grade plastic material. Lancet 72 k may be constructed of any suitable material adapted for puncturing the skin, and is typically a surgical grade metal such as stainless steel.

Rear cap 24 k of housing 12 k further comprises internal structure adapted to interact with plate 262 to cause actuation of lancet device 10 k. In particular, rear cap 24 k is formed with at least one and typically two distally-extending actuation members typically cam elements 280 each having a tapered cam surface 282 formed on their distal ends. Cam elements 280 are formed to extend distally into the respective cam guide recesses 268 in plate 262. The cam interaction between cam elements 280 and plate 262 provides the means by which the interference engagement between the lancet 70 k and plate 262 is removed to allow lancet 70 k to move to the puncturing position. More particularly, the interaction between the tapered cam surfaces 282 on cam elements 280 and cam guide recesses 268 in plate 262 during the retracting movement of shield body 50 k into main body 20 k causes sufficient rotational movement of plate 262 relative to carrier body 76 k to allow actuation tabs 81 k to align with clearance slots 264 in plate 262 to remove the interference engagement between lancet 70 k and plate 262. As indicated previously, such rotational movement of plate 262 is sliding rotational movement on rear rim 63 k of shield body 50 k. Also as indicated previously, guide slots 266 in plate 262 are preferable sized sufficiently to allow plate 262 to rotate to the alignment position without guide tabs 78 k interfering with such rotation.

Due to the elongated length of cam elements 280, shield body 50 k defines opposed cut-outs or notches 284 to accommodate the distal tips of cam elements 280 extending through cam guide recesses 268 in the initial, pre-actuated state of lancet device 10 k, and the eventual forward position of the distal tips of cam elements 280 as shield body 50 k is retracted into main body 20 k to cause actuation of lancet device 10 k. Cam guide recesses 268 are initially offset from notches 284 but as plate 262 is rotated to the alignment position cam guide recesses 268 eventually align with notches 284 as shown in FIG. 62. The engagement of cam elements 280 with plate 262 in cam guide recesses 268 provides an additional advantage of maintaining or locking the orientation of plate 262 on rear rim 63 k of shield body 50 k. Thus, plate 262 will be prevented or inhibited from disengaging from and falling off of rear rim 63 k should lancet device 10 k be turned upside down (i.e., shield 14 k pointed upward) prior to use. Additional structure extending from rear cap 24 k or internally from the inner wall of main body 20 k of housing 12 k may be provided to maintain the positioning of plate 262 on rear rim 63 k of shield body 50 k.

Additionally, in order to prevent the possibility of rotational motion imparted to plate 262 by cam elements 280 from being transmitted to shield body 50 k, shield body 50 k may comprise longitudinally-extending outer ribs 288 which are adapted to cooperate with interfering structure on the inner wall of main body 20 k, such as an engaging tab or detent (not shown). The engagement of such a tab or detent with ribs 288 will substantially lock the orientation of shield body 50 k relative main body 20 k and prevent rotation of shield body 50 k relative to main body 20 k. Moreover, engagement ribs 288 may be used as guiding structure to guide the retracting movement of shield body 50 k into main body 20 k during actuation of lancet device 10 k. Shield body 50 k further defines an abutment shoulder 290 at forward end 52 k. Abutment shoulder 290 is adapted for interference engagement with forward rim 42 k of main body 20 k to prevent shield body 50 k and, thus, lancet 70 k from axial forward movement out of main body 20 k through front opening 30 k. Additionally, the limited positioning or biasing force of drive spring 92 k on lancet 70 k in the initial, pre-actuated state of lancet device 10 k is transmitted by the interference engagement between plate 262 and shield body 50 k to shoulder 290, which then engages forward rim 42 k.

Use and actuation of lancet device 10 k will now be described with continued reference to FIGS. 56-67. Lancet device 10 k is typically initially provided with cover 100 k extending distally from carrier body 76 k, and through forward opening 60 k in forward end wall 58 k of shield body 50 k. In the initial, pre-actuated state of lancet device 10 k, drive spring 92 k is typically uncompressed between the inner side of rear cap 24 a and proximal spring guide 86 a of carrier body 76 a, and lancet 70 k is initially in interference engagement with plate 262, for example under the limited position or biasing force provided by drive spring 92 k. In particular, actuation tabs 81 k extending from carrier body 76 k rest upon the upper side 270 of plate 262 and are offset from mating clearance slots 264 in plate 262. Further, in the initial, pre-actuated state of lancet device 10 k, guide tabs 78 k are disposed in guide channels 80 in shield body 50 k, and extend proximally through guide slots 266 in plate 262. As indicated previously, the engagement of guide tabs 78 k in guide channels 80 k prevents rotation of lancet 70 k in shield body 50 k and, more particularly, carrier body 76 k in shield body 50 k during the rotational movement of plate 262 used to release the interference engagement between actuation tabs 81 k and plate 262, as described herein. Cam elements 280 extending distally from rear cap 24 k extend at least partially through the respective cam guide recesses 268 defined in the periphery of plate 262. Typically, the tapered cam surfaces 282 of cam elements 280 contact plate 262 within cam guide recesses 268 to allow cam elements 280 to effect the rotational movement of plate 262 when shield body 50 k is retracted (i.e., depressed) into main body 20 k, and secondarily to maintain plate 262 associated with rear rim 63 k of shield body 50 k. As described previously, guide slots 266 in plate 262 are sized to accommodate guide tabs 78 k and to allow plate 262 to rotate relative carrier body 76 k without guide tabs 78 k interfering with such rotational movement necessary to allow actuation tabs 81 k into alignment with clearance slots 264 in plate 262. In this initial, pre-actuated state of lancet device 10 k, cam guide recesses 268 are offset from notches 284 in shield body 50 k with the only the distal tips of cam elements 280 extending through cam guide recesses 268 as shown in FIG. 65B.

To use the lancet device 10 k, the user grasps opposing sides of housing 12 k, such as between a finger and thumb, and removes breakable cover 100 k. Cover 100 k is removed typically by moving cover 100 k in a combined twisting and pulling motion in forward opening 60 k in forward end wall 58 a of shield body 50 k to break the frangible connection with carrier body 76 k. Once the frangible connection is broken, cover 100 k may be removed through the forward opening 60 k. Forward end wall 58 k of shield body 50 k may then be placed in contact with a location on the patient's body where it is desired to cause a puncture injury to initiate blood flow. If provided, target indicia may be aligned with the desired location of puncture.

Once placed against the body, the user exerts a downwardly directed force on main body 20 k of housing 12 k forcing shield body 50 k of shield 14 k to retract (i.e., depress) into housing 12 k. In particular, the user applies a downward directed force in the direction of Arrow X, thereby applying a force against the user's body (i.e., skin surface). Such force establishes an opposing force on forward end wall 58 k of shield body 50 k causing shield body 50 k to retract axially within main body 20 k of housing 12 k. As shield body 50 k retracts into main body 20 k, rearward end 54 k of shield body 50 k moves proximally (i.e., rearward) toward rear cap 24 k. The engagement between rear rim 63 k at the rearward end 54 k of shield body 50 k and plate 262 causes plate 262 to move together with shield body 50 k toward rear cap 24 k. As the entire lancet 70 k moves rearward due to the interference engagement between actuation tabs 81 k and plate 262, drive spring 92 k begins to compress or compresses further between rear cap 24 k and carrier body 76 k and, more particularly, between proximal spring guide 86 k and rear cap 24. Substantially simultaneously, cam elements 280 interact with plate 262 in cam guide recesses 268 in plate 262, and act upon plate 262 to cause plate 262 to slidably rotate on rear rim 63 of shield body 50 k. In particular, as shield body 50 k moves proximally, tapered cam surfaces 282 on cam elements 280 engage plate 262 in cam guide recesses 268 causing plate 262 to rotate. The tapered form of tapered cam surface 282 converts the linear retraction motion imparted to shield body 50 k to rotational movement of plate 262. The engagement of guide tabs 78 k in guide channels 80 k prevents lancet 70 k and carrier body 76 k in particular from rotating in shield body 50 k. As shown in FIG. 66B, the distal ends of cam elements 280 project further through cam guide recesses 268 as cam elements 280 rotate plate 262 toward the release position where actuation tabs 81 k align with clearance slots 264 in plate 262.

As the entire lancet 70 k continues move rearward due to the interference engagement between actuation tabs 81 k and plate 262, drive spring 92 k continues to compress between rear cap 24 k and proximal spring guide 86 k, and am elements 280 continue to rotate plate 262 on rear rim 63 k of shield body 50 k. Eventually, plate 262 rotates to the release position where actuation tabs 81 k align with clearance slots 264 in plate 262, as shown in FIG. 67B. When this occurs, the interference engagement between actuation tabs 81 k and plate 262 is released. At the moment the actuation tabs 81 k align with clearance slots 264, the restraining force applied to drive spring 92 k due to the interference engagement between actuation tabs 81 k and plate 262 is released, releasing the stored potential energy in drive spring 92 k as kinetic energy used to move lancet 70 k forward in shield body 50 k. With the stored potential energy in compressed drive spring 92 k released as kinetic energy, drive spring 92 k biases lancet 70 k away from rear cap 24 k and through internal cavity 56 k in shield body 50 k. During such movement, corresponding guide tabs 78 k and guide channels 80 k guide lancet 70 k axially through shield body 50 k. The biasing force acting on lancet 70 k is preferably sufficient to cause the puncturing end 74 k of lancet 72 k to project a sufficient distance and with sufficient force from the forward opening 60 k in shield body 50 k to cause a puncture wound in the desired location on a patient's body. Moreover, during the propelling axial movement of lancet 70 k, proximal spring guide 86 k on carrier body 76 k of lancet 70 k releases from drive spring 92 k which remains connected to rear cap 24 k. In lancet device 10 k, lancet 70 k is limited to axial movement only with respect to shield 14 k and housing 12 k.

Moreover, as lancet 70 k moves forward in the propelling movement, distal spring guide 88 k engages the rearward end of retraction spring 94 k. The biasing force provided by drive spring 92 k is at least in part applied to retraction spring 94 k by engagement of distal spring guide 88 k with the rearward end of retraction spring 94 a which causes retraction spring 94 k to compress toward distal end pocket 98 k and store potential energy. Retraction spring 94 k is designed such that it may be compressed in whole or in part by the biasing force of drive spring 92 k propelling lancet 70 k, but still permits puncturing end 74 k of lancet 72 k to extend through forward opening 60 k in shield body 50 k a sufficient distance and with sufficient force to puncture the skin of the patient and initiate blood flow. Guide channels 84 k associated with actuation tabs 81 k may be formed with abutment surfaces for engagement by actuation tabs 81 k during the forward movement of lancet 70 k to prevent lancet 70 k from axial movement entirely out of shield body 50 k through forward or front opening 60 k. Alternatively, carrier body 76 k and/or distal spring guide 88 k may be adapted for interference engagement with forward end wall 58 of shield body 50 k to prevent lancet 70 k from axial movement entirely out of shield body 50 k through forward or front opening 60 k

As indicated previously, retraction spring 94 k is typically a compression spring and will have sufficient resilience to return to a relaxed, unloaded state within shield body 50 k after the lancet 70 k extends to the puncturing position. Accordingly, once the retraction spring 94 k is compressed it will provide a return biasing force on the lancet 70 k by engagement with the distal spring guide 88 k on carrier body 76 k. Retraction spring 94 k thereby acts between the forward end wall 58 k of the shield body 50 a and distal spring guide 88 k on carrier body 76 k to cause complete retraction of lancet 70 k into shield body 50 k. In particular, retraction spring 94 k applies a return biasing force that retracts the puncturing end 74 k of lancet 72 k entirely within shield body 50 k. Moreover, as the retraction spring 94 k returns to a relaxed or unloaded state within shield body 50 k, lancet 70 k is returned to a static position within shield body 50 k, wherein lancet 70 k is disposed at a relatively fixed and stationary position within shield body 50. Once retraction spring 94 k returns to a relaxed or uncompressed state, retraction spring 94 k maintains lancet 70 k disposed within the shield body 50 k with puncturing end 74 k shielded within shield body 50 k, and prevents further movement of lancet 70 k toward the puncturing position.

While the invention was described with reference to several distinct embodiments of the lancet device, those skilled in the art may make modifications and alterations to the invention without departing from the scope and spirit of the invention. Accordingly, the above detailed description is intended to be illustrative rather than restrictive. The invention is defined by the appended claims, and all changes to the invention that fall within the meaning and range of equivalency of the claims are to be embraced within their scope. 

The invention claimed is:
 1. A lancet device, comprising: a housing; a shield at least partially disposed within the housing and movably associated therewith; a lancet disposed in the housing and axially movable through the shield and comprising a puncturing element, the lancet adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure; a drive spring disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position; and an actuator associated with the shield and in interference engagement with the lancet in the initial position, the actuator including at least one breakable shelf in interference engagement with the lancet and a sleeve extending from the at least one breakable shelf toward the forward opening in the shield, wherein a portion of the sleeve is disposed between the shield and the housing; wherein axial movement of the shield and the actuator into the housing causes the actuator to move the lancet toward and contact the rearward end of the housing to at least partially compress the drive spring, and wherein upon contact with the rearward end of the housing the force applied to retract the shield into the housing causes failure of the interference engagement between the actuator and the lancet thereby releasing the at least partially compressed drive spring and permitting the drive spring to bias the lancet through the shield to the puncturing position.
 2. The lancet device of claim 1, wherein the sleeve extends axially along an outer surface of the shield, and wherein the sleeve is configured to receive a rearward end of the shield.
 3. The lancet device of claim 2, wherein an inner surface of the sleeve engages a proximally extending portion of the outer surface of the shield.
 4. A lancet device, comprising a housing; a shield at least partially disposed within the housing and movably associated therewith; a shearable element including at least one internal tab and a sleeve, the shearable element movably engageable with the shield; a lancet disposed in the housing and axially movable through the shield and comprising a puncturing element, the lancet adapted for axial movement between an initial position wherein the puncturing element is disposed within the housing and a puncturing position wherein the puncturing element extends through a forward opening in the shield for a puncturing procedure, the lancet in interference engagement with the internal tab in the initial position; and a drive spring disposed between a rearward end of the housing and the lancet for biasing the lancet to the puncturing position; the sleeve of the shearable element extending from the internal tab toward the forward opening in the shield and wherein a portion of the sleeve is disposed between the shield and the housing, wherein axial movement of the shield and the shearable element into the housing causes the lancet to move toward and contact the rearward end of the housing due to the interference engagement with the internal tab to at least partially compress the drive spring, and wherein upon contact with the rearward end of the housing the force applied to retract the shield into the housing causes failure of the internal tab removing the interference engagement and releasing the at least partially compressed drive spring to bias the lancet through the shield to the puncturing position.
 5. The lancet device of claim 4, wherein the lancet comprises a cutting element providing the interference engagement with the internal tab, and wherein failure of the internal tab is caused by the cutting element cutting through the internal tab.
 6. The lancet device of claim 4, wherein axial movement of the shield into the housing moves the shearable element into the housing and causes the lancet to move toward and contact the rearward end of the housing due to the interference engagement with the internal tab to at least partially compress the drive spring, and wherein upon contact with the rearward end of the housing the force applied to retract the shield into the housing causes failure of the internal tab removing the interference engagement and releasing the at least partially compressed drive spring to bias the lancet through the shield to the puncturing position.
 7. The lancet device of claim 4, wherein the shearable element is secured to the shield by an adhesive.
 8. The lancet device of claim 4, wherein the shearable element is secured to the shield by a mechanical locking engagement.
 9. The lancet device of claim 4, wherein the sleeve extends axially along an outer surface of the shield, and wherein the sleeve is configured to receive a rearward end of the shield.
 10. The lancet device of claim 9, wherein an inner surface of the sleeve engages a proximally extending portion of the outer surface of the shield. 